Dear Mark: Should I Consume Caffeine Before My Workout?

In today’s edition of Dear Mark, I cover a topic near and dear to many of your hearts: caffeine. But I don’t just cover caffeine; I explore whether caffeine truly does act as a diuretic, especially during exercise, and whether or not caffeine can actually be helpful to athletic performance. Should we all be downing mugs of joe or cups of tea before we hit the gym or head outdoors?

Let’s find out.

Dear Mark,

I’ve been told that drinking coffee prior to, or during workouts is a big no-no, because it’s a diuretic and will lead to dehydration, which is no good for performance (or health). But I love an iced coffee right before my workouts. I feel like it helps. It could just be placebo, but if it’s not hurting, I’m okay, right?

I wonder if you could give me the lowdown on what the literature says. Thanks!


First, let’s tackle the dehydration question. It has undoubtedly become “common knowledge” that coffee is a potent, perhaps the most potent, diuretic, that drinking it is like drinking negative water, and that if you’re stuck on a desert island you’d be better off drinking your own saliva than that steaming cup of joe from the Starbucks that inexplicably decided to set up shop on a desert island. Yeah, there are a lot of scary stories about coffee, but does it hold up to scrutiny?

No. A quick search on PubMed turns up a couple German-only studies with vociferously and unambiguously worded titles but no abstracts (“Coffee does not cause dehydration!” and “Coffee does not dehydrate. New studies of Germany’s favorite addiction: coffee.”), as well as some English ones with abstracts:

  • One from the University of Connecticut measured fluid, electrolyte, and renal indices of hydration over eleven days of caffeine consumption in human subjects. Doses of up to 6 mg caffeine per kilogram of body weight had no effect on body mass, urine osmolality (urine concentration), urine specific gravity (concentration of excreted materials in urine), urine color, urine volume, sodium excretion, potassium secretion, creatinine content, blood urea nitrogen (forms when protein breaks down), and serum levels of sodium and potassium, causing the researchers to conclude that caffeine does not cause dehydration.
  • Another compared hydration markers in patients who consumed either caffeinated beverages (coffee and cola), non-caffeinated beverages (coffee and other sodas), and/or water. The effect on hydration status was essentially uniform across all beverage categories, regardless of caffeine content.
  • And finally, a review from the American College of Sports Medicine found that not only does caffeine not reduce hydration nor induce electrolyte imbalances, it has no effect on heat tolerance during exercise.

I think that settles that. Caffeine does not dehydrate you or cause you to overheat. It’s “safe.” It’s not bad for the active athlete.

But is it actually good? Does it do anything except fail to dehydrate you?

Oh, yeah. Let’s dig into the literature to find out what it can do for your athletic performance.

Endurance Exercise

Most of exercise/caffeine literature centers on endurance training and performance. I remember back when I was running, the most oft-cited benefit to caffeine before a race or training was that it would increase the oxidation of fat, thus sparing muscle glycogen. That sounds nice and tidy, and it would be awesome if it were true, but the most recent evidence suggests that caffeine has little, if any, effect on fat or glycogen metabolism during endurance exercise. So what are we to make of the older evidence that does show a difference in fat oxidation after caffeine ingestion? Or the 1992 study that found caffeine reduced the tendency of muscle to burn glycogen early on during extended bouts of exercise, thus “sparing” it for later on?

It may be that caffeine simply makes exercise more tolerable, makes muscles work harder and better, and allows those exercising to do so harder. One study found that while pre-workout caffeine did not spare glycogen, it did boost the endorphin response to exercise. If endorphins are high, exercise is more tolerable, even enjoyable. If caffeine can increase the runner’s high, it’s also going to make exercise more effective and more self-perpetuating.

Whatever the case may be, the literature is pretty clear that caffeine improves endurance performance, perhaps by enhancing fuel partitioning or making exercise more tolerable and enjoyable.

Anaerobic Exercise

The extent of research into the effects of caffeine on anaerobic performance – think sprints, weight lifting, and interval training – is limited, but useful literature exists. One review, from 2009, noted that while caffeine appears beneficial to speed endurance training (in the realm of 60 to 180 seconds) and high intensity interval training (HIIT), it has limited use in power sports. It may help lower body muscle endurance, but it appears to have a minimal effect on the upper body. The authors propose a number of mechanisms for caffeine’s action, including enhanced calcium transport and the old fat utilization/glycogen sparing thing, but the most promising idea is that caffeine simply stimulates the central nervous system enough to blunt adenosine receptors, increase pain tolerance, and dampen perceived exertion.

What about resistance training? In one study, caffeine ingestion boosted trained women’s 1RM in the bench press (PDF). In another, caffeine seemed to have no effect. A review from 2010 determined that short-term, acute ingestion of caffeine is beneficial in team-based and power sports, but mostly in individuals who did not routinely ingest caffeine. Six of eleven resistance training studies reviewed in the study showed benefits to caffeine ingestion, so the evidence remains fairly equivocal.

Thus, when you drink coffee before lifting heavy things or sprinting, your performance will not suffer – and it may even improve.

It may even be a simpler, less exciting explanation than anything overtly physiological: that the “benefits” of caffeine to physical performance may actually be a cessation of the negative effects of caffeine withdrawal. As Sweat Science points out in a recent post, before double-blind trials on the effect of caffeine on performance, participants must abstain from caffeine for a day or two. If they’re habitual caffeine fiends (as many people are), by the time they begin the study they’re already suffering withdrawals. Studies on cognitive performance and caffeine have found that when you account for the withdrawal effect, caffeine has little to no benefit to performance. Researchers have yet to examine the withdrawal effect in studies on athletic performance, but it appears a likely candidate for at least some of the reported benefit to caffeine consumption.

It’s also important not to lose sight of the fact that most of us are drinking coffee, not popping pure caffeine pills. Coffee contains tons of polyphenols, bioactive compounds that could have beneficial (or negative) effects on exercise performance. Most of the studies are looking at caffeine, so they have to isolate it. But if you’re drinking coffee, shouldn’t you look for studies that examine coffee? There’s a recent one that found ingesting coffee polyphenols increased fat oxidation (PDF). Of course, the caffeine, polyphenol, and other bioactive compound contents of coffee are not stable. Coffee is a food made up of hundreds of factors. It’s not just a source of caffeine. Based on soil conditions, climate, elevation, roast, and variety of bean, two cups of coffee can display remarkably different characteristics, and it’s likely that the effects of each on exercise performance will also differ.

Bottom line, though: if coffee makes you perform better, keep drinking it before, during, or after you workout. At least we can say for sure that it’s not dehydrating you.

How does coffee affect  your workouts? Better? Worse? No effect? Let me know in the comments!

TAGS:  coffee, dear mark

About the Author

Mark Sisson is the founder of Mark’s Daily Apple, godfather to the Primal food and lifestyle movement, and the New York Times bestselling author of The Keto Reset Diet. His latest book is Keto for Life, where he discusses how he combines the keto diet with a Primal lifestyle for optimal health and longevity. Mark is the author of numerous other books as well, including The Primal Blueprint, which was credited with turbocharging the growth of the primal/paleo movement back in 2009. After spending three decades researching and educating folks on why food is the key component to achieving and maintaining optimal wellness, Mark launched Primal Kitchen, a real-food company that creates Primal/paleo, keto, and Whole30-friendly kitchen staples.

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143 thoughts on “Dear Mark: Should I Consume Caffeine Before My Workout?”

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    Regardless of how you came down on this issue, I wasn’t going to stop with my coffee. Nevertheless, I’m glad to see your report, which confirms what I already knew: Coffee is manna from heaven.

    1. haha, agreed. few things could stop my love of coffee at this point… but very happy to know it’s not bad for you 🙂

    2. Supposedley Bach had a caffeine habit.
      An inadequate question: Would you rather have your flame shine bright and burn fast, or smoulder and work its way through the boulders?
      As the fictional Col O’Neill says, it’s always better to have a big whick.

  2. All I know about coffee is that it makes me visit the bathroom often and leaves and dry mouth sensation.
    The smell and taste are great, but I indulge maybe 2 or 3 times each year. Chocolate is better! 😀

    1. Ditto for me! I rarely drink coffee but understand that most do and thus am experimenting with coffee smoothies.

      Coffee leads to fast and quick poops no doubt.

      I love the smell and enjoy it black too. I take a few sips here and there and enjoy it in coffee smoothies!

        1. Hahahaha! Oh my gosh, you have a good eye. I definitely didn’t notice that. Pretty hilarious XD

        2. I love the smell and taste of coffee! 🙂 Love, love, love! I just rarely enjoy it but I am on a coffee smoothie roll!

      1. ”Coffee leads to fast and quick poops no doubt.
        I love the smell and enjoy it black too”

        Oh, how i laughed!!

      2. Coffee inhibits fat digestion so if you have fat digesting and drink coffee it will force it out.

    2. Coffee is not an indulgence….it is a way of life. LOL, I’m just kidding, but there is no way I could only drink it 2-3 times per year. Good for you!

    1. I’ve seen “bullet proof coffee” a few times now between yesterday and today… it seems to be really catching on!

  3. Two problems with coffee:

    1) It’s addictive. I don’t want to anything in my body, especially a stimulant, that creates its own need.

    2) It negatively affects sleep and rest.

    3) It’s probably inflammatory to your internal organs

    I’ve switched to drinking herbal teas. A great way to get a wide variety of nutrients into your body. Coffee leaves may have nutritional value, but they are a mono nutrient if you consume the same plant every day.

    1. That looks like 3 problems:)

      What is your data source to support coffee’s inflamatory effect on internal organs?

      1. Don’t have one. However, it was on a list of inflammatory foods. I eliminated these foods from my diet (gluten, sugar, corn mainly) and my liver enzymes dropped back to normal and my cholesterol dropped back to normal. So I just have my own experience to draw on. Maybe coffee wasn’t causing the inflammation, but I have enough reasons to stop anyway i.e. don’t like being addicted a stimulant. I have horrible withdrawal symptoms, mostly bad headaches.

      2. There’s 3 kinds of people in the world, those that can count and those that can’t.

    2. 2) Dig around for yourself but this is one of those oft cited myths. Its true initially, but once tolerance develops the effect on sleep doesn’t exist. I’m sure everyone can think of a friend that has coffee after dinner and sleeps an hour later.

      3) Do you have any source for this or do you just think this? Countless studies spout caffeines benefit to the brain and reduced risk of colon cancer. Even if it “irritates” your bowels, its way less than gluten or other major grains. If you’re abstaining from grains and eating plenty of good fat and vegetables, your organs are more than fine enough to handle caffeine.

      Number 1 is your only truly valid concern.

      1. I can see where coffee leads to a reduced risk of colon cancer. I don’t drink coffee often at all but since I know so many do, I am creating coffee smoothies for my ebook.

        After I consume the coffee smoothies, I really have to… go! It comes out nice and easy and fast. It’s a good poop.

        Is coffee healthy? It depends.

      2. Chris – caffeine sensitivity can develop for some people, especially as they age. For other people, that doesn’t happen.

        I am very caffeine sensitive – but I have a friend a few years older than me (63) who drinks large mugs of coffee at bedtime and sleeps like a baby. If I drink one 6 oz cup of regular coffee in the AM, it disrupts my sleep that night.

      3. Actually, I think some people are sensitive to coffee’s effect on sleep. I used to drink coffee regularly, so I had built up a certain amount of tolerance. Nonetheless, if I drank some after a certain time (which got to be earlier and earlier), it definitely kept me awake. And it wasn’t in my head because there were times when I’d ask for decaf out and would be jittery and wakeful anyway, indicating the barrista likely forgot and made it regular. Since I was expecting decaf and no such effects, it couldn’t have been in my head! My mother was ultra sensitive to the effects as well and ultimately had to give it up. I still drink caffeinated in the morning, but after 2 or 3 PM, I can’t. Likewise strong chocolate. I can’t eat it in the late afternoon or evening without paying the price when it comes time to sleep. Not everyone is as sensitive–my husband isn’t–but some of us are.

    3. I only have about 1.5 cups of black every morning AFTER 40 oz of water. No sleep problems since I don’t have it after 7 am. drinking it all day is a dreadful idea for a multitude of reasons. Small amounts are good for you, although I bet all day dependency probably is inflammatory to some extent. And to echo many others here…yes, it gets things moving nicely. And delicious!

    4. Coffee comes from beans, not leaves. Thus your whole comment is subject to question.

    5. I agree big time on the first two points you’ve brought up. Anything you just ‘can’t live without’, regardless of its influence on internal health, can’t be good for overall well being (It might be aiding your training but what about your mood, behavior, stress levels etc.)?

      If our body becomes less sensitive to stimulants as exposure continues, it makes sense that drinking coffee on a regular basis would cause us to require more of the stuff to get that same ‘pick me up’.

      I think there are better (more Primal) ways to get a pick me up than having to rely on an addictive substance like coffee(but hey, that’s just me)

      1. >>Anything you just ‘can’t live without’, regardless of its influence on internal health, can’t be good for overall well being<<

        Really? Because I can't live without water. And yes, I get major headaches if I don't drink enough water.

  4. Coffee helps me on the occasions when fasted workouts feel unappealing. Sometimes I drink decaf, and for some reason I never notice the affect of caffeine (unless trying to sleep), and they both make me pee more!

  5. Given the plethora of caffeine-based energy drinks available, I don’t see why a person would drink coffee before a workout, even if it is iced coffee, an energy drink can provide adequate caffeine while being easier on your stomach. I like coffee as much as anyone but I don’t understand how drinking it before engaging in intense physical activity is going to yield good results.

    There are a lot of review sites online that discuss caffeine content, flavor etc. of the various energy drinks.

    Personally I like Rock Star Low Carb, which contains substantially more caffeine than their Sugar Free drink.

    1. The only way that energy drinks would be considered Primal is if you could point out the Rock Star shrub or Monster plant where the ingredients came from.

      Are you kidding me? With the amounts of sugar/sweeteners and sodium in those things?

      Don’t get me wrong, prior to going Primal, I used to drink at least one of the big cans of Rock Star every day. They’re delicious, but they’re certainly not Primal in any sort of way.

      Energy Drinks are the epitome of processed food/drink.

      1. If they assist in getting a better work out what difference does it make if they are primal?

        All supplements are non-primal and are highly processed.

        1. Stop trolling. ‘Who cares if it’s primal?’ Seriously? Rockstar drink is a perfect example of the crap that is killing people slowly.

        2. I suppose you could say the same thing about Cocaine, Meth, or Steroids.

          If they assist in getting a better work out, what difference does it make?

          They’re not healthful – quite the opposite, actually. That’s the difference.

      2. Right on Jason, the people that are constantly asking “Does that food clash with my loincloth?” really chap my ass redder than a boar skin loincloth with the hair turned to the inside!

  6. I’ve been weight training since 2002 and noticed early on that drinking a strong cup of coffee before workouts directly influenced my motivation. I have no proof that the caffeine made me lift heavier, but there is no doubt in my mind that the coffee boost made me more energetic and helped remove the “*sigh*.. here we go” kinda feeling when entering the gym =) (I know, skip some workouts now and then!)

    Today I roast my own coffee and it’s a big part of my life, so as an avid MDA reader I’m especially happy that Mark approves 😉

    Thanks again for yet another informative and entertaining article!

  7. Coffee doesn’t even taste very good. I think it’s the addiction that makes people think they like. It does zero for me. Much like cola, I don’t think cola has any redeeming attributes and the flavor certainly adds nothing. If I want to put crap in my body give me some grape soda or even kool aid.

    1. I LOVE the taste of coffee. Absolutely love it. Black. Am I addicted? Well, let’s see…

      Throughout this entire year I have enjoyed a few sips of family members coffees and 2 coffee smoothies that I created.

      I’m far from addicted. I don’t drink coffee but I LOVE the flavor. I think many others are in the same boat as me.

      1. Agreed! Black is what I go to, but almond milk lattes rock. It’s all taste for me. Love the flavor!

        1. I have my one cup per day with home-ground espresso beans, a teaspoon of honey, and a HUGE glob of coconut cream. OMGSOGOOD.

          Best part of brunch.

    2. Since I drink mostly decaf, I’d say it’s about taste for me. But I only drink espresso, not regular coffee, and I love it in smoothies. So no, it’s not the addiction.

  8. I love my morning coffee, and drink a cup 45-60 minutes before my morning workout, but before breakfast.

    This routine has worked for me, but I’ve always had the nagging feeling I should investigate if this was really wise. Thanks for putting that worry to bed for me!

  9. I’ve been having a big cup of black coffee before my full body workouts at the gym for about a year now. YES, there’s definitely a difference. Even if there weren’t a physical performance benefit, concentration is most certainly better when there’s caffeine in the system. Nice to hear it doesn’t dehydrate, though!

    For me, coffee + creatine monohydrate (micronized) + aggressive music = a very successful and satisfying workout every time 😀

  10. I love coffee, the taste, the smell, everything. I can drink a cup of the strong stuff before bed and it doesn’t affect me, neither does it wake me up in a morning. I can go for weeks without it and not have withdrawal. This doesn’t mean everyone should drink the stuff just because it’s fine for me. I guess what I’m saying is everyone is different. You don’t have to give up coffee just because it affects someone else in a certain way, if it’s the caffeine that affects you, drink decaffeinated. If you don’t like the taste, great. Don’t drink it. But don’t use that as a reason to tell everyone else why they like it!

  11. As part of my dietary cleanup, I examined my daily, heavy (almost a pot) coffee habit. It may have been the low-carb, but I was noticing that the caffeine was doing more harm than good: blood-sugar like crashes, occasional mood disruption, and the expense/inconvenience of brewing. Couple that with the classic ‘I need my coffee’ addiction rationalization, and I decided to 86 it.

    I’ve felt much better having done so. I now drink tea (mostly green) when I need a body warmer.

    To the coffee junkies: maybe take a few weeks off (the first few days suck a bit) and see how you feel. It’s nice to not feel dependent on a stimulant.

      1. It’s the appropriate word. Frankly, I don’t understand why Mark would post something like this that legitimizes a caffeinated drink. The market is being flooded with “energy drinks” that are poisoning our youth. Do you know how many people are using these drinks as meal replacements?

        Caffeinated drinks are useless and detract from your health.

        1. Actually, I’m pretty sure he’s talking about COFFEE.

          Just because pizza has vegetables and meat on it does not mean that Mark is endorsing Pizza as primal.

          COFFEE comes from a plant. It’s roasted, much like your macadamia nuts.

        2. Coffee and caffeinated drinks are not interchangeable terms. Do you understand the point of this website? Coffee does not have sugar in it in its natural form.

        3. Doug…coffee is more than a “caffienated drink”. Mark is not advocating anything other than coffee. Is it beneficial. How about cutting your diabetes Type 2 risk in half with 4 cups per day. How about..”if you are an alcoholic and you drink 1-2 cups of coffee a day you risk of cirrosis of the liver drops more than 20%. If you are an alcoholic and you drink 4-6 cups a day your risk of cirrosis drops over 80%.” Coffee is protective of the liver. You can’t live without a liver.
          These are the first 4 out of 42….pass the joe!

        4. I’m starting to think the point of this website is to tell bodybuilders what they want to hear.

          When it comes to hot drinks, anybody who cares about nutrition would strongly advise people to drink a variety of organic, fresh herbals teas.

          Even if you leave out the caffeine addiction issue, drinking the same plant everyday is not paleo at all. Cavemen were foraging omnivores who thrived on a diverse diet of plants.

          I like almost everything about where Mark is coming from, but this post is a mistake.

        5. Those caffiene drinks you are referring to are not the same thing as drinking coffee, how about doing some research before you post your random bull$#*!.

          Yes there can be some issues with large consumptions of coffee, but moderation is rule with just about everything. Site your legitamate references stating that all caffeinated drinks are useless and detract from your health….don’t worry I’ll wait.

          While your getting that, read this…

          Doctors telling you the benefits of drinking coffee and all of their sources for the information included. So don’t come on here bad mouthing something that you aren’t backing up.

          And don’t try and blame this on me being a coffee drinker…..I don’t like the taste of coffee, like you I’m a tea drinker.

    1. Obviously if you drink a pot of coffee its not good. Coffee in the morning is harmless. Yes it is 100% a diuretic…not rocket science. It makes you pee like a race horse. Will it dehydrate?… no not 1 cup. Boy common sense people! Feel like I’m reading a bunch of neurotics here.

  12. I have never drunk coffee and probably never will. Although, I am about to start drinking homemade kombucha before, during and after workouts, which I believe would be more beneficial.

    1. I used to say this same thing. I don’t drink coffee much but I do LOVE the taste. No sugar, no cream. Just straight up coffee.

      Coffee smoothies rock my world.

  13. Coffee is weird, after giving it up as a habit, 95% of the time, I find the smell, taste and idea of coffee unpleasant.

    But sometimes that bitter smell just seems irrestistable and, if I do decide to buy it, I love the first and second sip, then it just becomes a chore…

    I used to pour coffee powder (extra-fine) into whipped cream/ creme fraiche. But not before a workout. That would be horrible.

  14. i always wondered if the difference in studies on coffee were because some used arabica and some used robusto. the latter has a significantly higher caffeine content and probably different quantities of other phytochemicals as well.

    i like to be able to use coffee as a stimulant, which becomes impossible when you’re addicted. therefore, decaf use for “everyday” and the high-octane stuff for times when i need a boost fit my style very nicely.

    1. Yes, regular decaf consumption – and then caffeinated coffee only just before a workout should preserve the benefits. That’s one of my take aways.

  15. The thing is that the studies are about COFFEE not caffeine. The difference is that there is much more to coffee then just caffeine. You don’t get the same benefits from caffeine as you do coffee. Everyone is talking about caffeine and excluding everything else.

  16. As others here have said, caffeinated coffee makes me pee more – decaf does not. As the cited studies used isolated caffeine, maybe the diuretic effect is a combination of caffeine and some other substance in coffee.

    At any rate, I don’t find the diuretic effect to be more than mild and adequate water intake maintains hydration. I don’t drink coffee because – as some, but not all people find – I have become more sensitive to caffeine as a stimulant as I age. Going primal only made that sensitivity more marked. If I consume ANY caffeine even early in the AM it disrupts my sleep.

    But, I wonder if I only consumed caffeine directly before exercise if it would have the same effect. I may try drinking a cup of coffee before my morning walk and see what happens. Hopefully, it won’t shorten my walk by making me head for a bathroom :-).

  17. When I went to Cyprus on holiday, I saw that people there, even in the middle of the summer, drank very strong Cypriot coffee. I went on a mountain biking trip and when we sat down for a break at some small ‘kafeneion’ in the mountains, they gave us coffee. However, they ALWAYS serve a tall glass of water with your coffee.

    1. Well, there you go! What’s wrong with a kidney flush anyway? We detox the liver why not detox the kidneys?

  18. Decaf for me. Most of the time. Really, it’s just a cream delivery mechanism!

    So, does that make me an addict or junkie? I’m not getting caffeine, but I drink quite a bit of coffee anyway. I guess I’m weird that way, huh?

    1. My decaf is a coconut creme delivery system :-). Part of my thyroid support plan. It would be a cream delivery system if I were doing dairy. Maybe once I find a local source of raw cream I’ll give it a go. Really would be interesting if my dairy allergies weren’t activated by raw dairy. Its been pretty dreary all these years without cream.

  19. I find it interesting to hear the different points of view.

    I absolutely love the taste of coffee, but I don’t drink just any old stuff; it has to be a very specific type and the way it is made is crucial. In the morning I use a french press with a medium roast, usually from Mexico, Guatemala or Kenya, with heavy cream and a touch of honey. In the mid morning or afternoon I will have an espresso.

    I am totally addicted to coffee…. out of all the things I have given up it is one of the things I am most stubborn about. At this point having heard nothing conclusive either way I will continue with my addiction. 🙂

    That being said… coffee makes me extremely anxious and irritable to drink too much of it. I don’t drink more than two cups a day and I don’t typically drink it after 2pm because it does impact my sleep.

    Since the point of this article is caffeine and exercise, I will say this: if I drink it and do endurance exercise I end up in the bathroom (or the bush) ASAP. If I drink it before resistance or sprints it gives me a little boost but it doesn’t last.

    1. Here’s a way out. Start mixing in decaf coffee with your regular coffee. Do it as slowly as you like, depending on your addiction level. Gradually increase the decaf until is is all decaf. Whole Foods sells a chicory based coffee substitute. Start drinking decaf one day, then chicory the next. Gradually shift to all chicory. Then start drinking a cup of herbal tea a day. Slowly shift from the chicory drink to all herbal teas.

    2. I agree with you. I LOVE MY COFFEE and am willing to change most everything about my lifestyle, but I won’t go without my morning ritual coffee. I also agree that 2 cups is the limit. When I have more than that I feel a change that is definitely no good. I am able to run after drinking coffee, but usually I have a tall glass of water first, then a cup and a half of coffee over an hour or so. By this point I have had to pee at least once, and I make sure to go again before heading out the door with my running shoes on. If there’s been a good hour between coffee and the run, there are no side effects at all.

    3. You know, if you do decide to go decaf, there are lots of gourmet decafs available. Swiss water method. No solvents. Organic. Sustainable. Flavored. Micro roast. Whole bean.

  20. My theory is that people feel like they are becoming dehydrated because the caffeine acts as a vasoconstrictor. This can produce much the same symptoms (like headaches) in people who are more sensitive to it.

  21. “Goddess of Addiction” and I LOVE HER!!

    You know that famous logo on Starbucks cups. I call her the “Goddess of Addiction” and I LOVE HER!!

    With this Paleo lifestyle of mine, black americanos are my only vice.

    How black americanos can be a comfort food, I don’t know, but they are.

    Thanks for the research!!

  22. I second Andreas. Drinking an espresso (with heavy cream) before workouts improves my lifting. No idea wether it’s placebo effect or not, it doesn’t really matter to me 🙂

  23. I wasn’t a big coffee drinker, pre primal(up to 2008)

    Since 2010 I’ve had 5-6 cups of strong, black french press. (It helped me keep going up to my first food at about at about mid day.)

    My TC, 2007 pre primal, approx 220.
    TC Nov 2011 ….530 !!

    Stopped all coffee. TC now 220 again.

    1. YES! I just read about that effect – with unfiltered coffee. I don’t use a paper filter but a permanent filter. It doesn’t filter the coffee the same as a paper filter. Can leave some grounds like boiled coffee. So that may be why I’ve recently had mysterious elevations in my TC, LDL, and triglycerides – it does all three. Whole ‘nuther reason for me to stop coffee.

  24. After three years of table tennis training, the only think that helps my endurance in a long session of multi-ball/footwork drills is a cup of coffee about two hours ahead of time. No foods, smoothies, supplements helped me. I would be pooped and have to take breaks so I could catch my breath. No more.

  25. I love coffee, but haven’t noticed much of a difference surrounding my workouts other than being more awake if I was a little groggy before coffee. I did notice being more energized after drinking more than usual before a long day hike (this could have been the fresh air and sun light though).

    I saw something about coffee increasing stress hormone somewhere (specifically Cortisol). I was hoping it would be mentioned in this post, does anyone know if there is any truth to an increase in stress hormone release from caffeine? specifically coffee?

    1. Yes, I’m shocked no one mentioned cortisol!! Coffee increases Cortisol which is why I drink mostly Green Tea (it does not). Cortisol is related to stress/aging and fat retention. I do LOVE espresso with a little coconut milk and the kick it gives my workouts but I limit it b/c of Cortisol and how it amps up my hyperhydrosis. The only Crotisol studies I’ve seem were from Dr. Pericone. Not sure on his credibility…

  26. What is missing here is a longitudinal analysis. It is one thing to do a study of a bunch of young healthy coffee drinkers and see what it does to their workouts. It is a whole other matter to see what a 3 cup a day habit does to your adrenals over a 20 year timeframe. And where does this fit into the acidity/alkalinity environment and inflammation? In the end it is always a matter of choice. I don’t think Grok downed a cup a Joe before heading out to snag dinner. But if the point of your workout is to get performance and PR’s and caffeine is a legal way to get there, so be it. However, at some point you need to think about the telomeres at the end of your DNA – at what point does caffeine to work out harder just shorten your life?

  27. I’m drinking a nice big cup of coffee as I read this, and I had one this morning before my workout. Glad to see it’s not detrimental to my workouts.

  28. I drink coffee before, during and after CrossFit workouts and can attest without a doubt that it absolutely improves performance, especially at 5:30 in the morning. Coffee rocks!

  29. I dig a coffee, never been addicted, never had withdrawal when I’ve drunk it regularly. I did try chucking it once before I went Primalish because I was having such bad gut issues. (And by that I mean, the shits, all the time.) But now that I’ve kicked the grains habit, coffee doesn’t affect me other than the really good poop thing. It never really occurred to me to have a coffee before a morning workout, but now that that’s out there as okay, I might just do that, because I usually have to wait for the uh, morning poop to have a good workout and coffee definitely … moves things along.

  30. My experience seems to indicate that reaction to caffeine is a uniquely individual experience. A long time ago, I finally figured out that most of my bouts with insomnia could be attributed to having consumed too much caffeine in one form or another after 3 PM. To this day, if I’m at a party or just don’t think about it and have too much chocolate or a cup of tea after about 3 PM, sure enough, I find myself too wired to sleep that night. But I know lots of people who drink coffee before going to bed with no problem whatsoever.

    I don’t care for coffee myself, but I also learned many years ago that a diet coke when I was dragging on a long bike ride would perk me right up and have me passing my fellow riders. My husband would always notice right away when I’d sneaked some serious caffeine on a ride because he would begin to have trouble keeping up with me. He’s tried it, and it doesn’t do a thing for him.

    I generally don’t ingest much caffeine, maybe one square of dark chocolate in the morning most days of the week, just because I like chocolate, but it doesn’t seem to give me the kick that a diet coke or caffeinated energy drink would give me. I’m not sure what I’ll do this summer when I need that kick on a bike ride since I’m now trying to live primally. Hopefully I’ll find I won’t need it

  31. I typically drink a cup of coffee about an hour or so before I workout. To combat dry mouth sensation, try chewing gum during your workout.

  32. I’m a HUGE advocate for pre-workout coffee.
    It works just as well as any pre-workout supplement on the market.
    Always a controversial subject of course, but it’s great to have the hard data.
    Nice one.

  33. I used to drink the mega-hyped pre workout stims like n.o explode, jack3d, n.o shotgun (don’t judge me, sucker for marketing). They did the job, gave me energy to hit the gym and hit it hard. But now I just mix a cup of black coffee in my pre workout shake. Does the job. And better on the wallet.

    Carry on.

  34. I take advantage of the perks of caffeine before/during races (Olympic/Half IM Triathlons). I definitely believe that caffeine helps tremendously during endurance races. I usually take gels with a caffeine supplement throughout the race. I feels like it gives me a boost of speed and my pain threshold seems to reduce.

    For everyday training, however, I tend to avoid drinking coffee before intense workouts (TTs on the bike/running intervals). The elevated heart rate becomes more uncomfortable and too stressful due to the caffeine during interval sessions. I can handle the stress on race day but not for everyday training. I also feel a lot better post workout without the caffeine in my system.

  35. Coffee and caffeine are NOT synonymous!

    I’ve found that decaf coffee has the same “moving” effect on my gut as caffeinated and perks me up about the same too. Add to that, I could (but no longer do!) drink a 20oz non-diet Mountain Dew right before bed and have no problems getting to or staying asleep. But coffee, even decaf in larger quantities, much after lunch, and I’ll be up for hours.

    These days my coffee is at most either two cups during the morning at work (one teaspoon of raw sugar and a dollop of whole milk) or else one homemade latte with a smidge of honey and vanilla (I’ve recently found where I can get raw Jersey milk and goat milk). I tried it with almond milk, and maybe it was that particular milk, but I thought it was singularly nasty.

    I haven’t tried drinking coffee or caffeine specifically for workouts, but anything that can help with motivation can’t hurt. As far as hydration, I don’t find coffee makes me pee anymore than an equivalent amount of plain water.

  36. I find that if I drink a cup or two of delicious coffee AND a couple full glasses of water, wait an hour before running and let some of that water make it back out, then my workout doesn’t end up with dry mouth or having to pee. I think you just have to find what amount of water and coffee works for you, and you CAN’T have just drank two cups in a half hour and then go. You have to pee first at least once. Coffee makes my workouts five times easier.

  37. I don’t drink coffee very often because it actually makes me sleepy, with the exception of a frappe like 2 hours before bedtime. Then I’m super hyper. I’m sure it’s got something to do with the high amounts of sugar. Plus, I don’t really like the smell of it, especially the first thing in the morning.

  38. Hmm…that’s strange. I absolutely love the taste of coffee and drink a cup of black coffee on my rest days, but whenever I consume any sort of caffeine on a workout day I perform horribly.

    Before I went primal, any form of caffeine – soda, energy drinks, coffee – would make me less coordinated when I played sports. That being said, the sports I did (badminton and martial arts) all required lots of precise movements, so maybe that was why caffeine had a negative effect. Too much arousal isn’t good for mentally difficult/complex activities, or at least that’s what my old psychology textbook told me.

    I’m not absolutely sure if my performance worsens while lifting heavy weights since I’ve recently been avoiding caffeine on workout days, but I have a feeling my power cleans won’t be as good because of the complexity of the exercise. I guess I’ll try drinking coffee on a weightlifting day a few times just to see what happens.

  39. I love a cup of strong hot coffee in the morning, it does wonders to perk me up.

    I gotta be at work at 7:30am everyday. ‘Gimme my coffee or I will hurt you.’

  40. Read the latest online edition of life extension magazine…they have a fantastic article of the great benefits of multiple cups of coffee a day….I myself am hardcore…I will put 2 tsps of instant coffee directly in my mouth and chase it with water…too lazy to heat the water and clean the cup….works for me…lol

  41. I’m pretty sure that caffeine increases the risk of arrhythmias during long periods of exercising- long runs for example (10+ miles).

    1. Yeppir! PVCs like crazy. No thank you, Mr. Coffee.

      Extra potassium for me and I feel great. Personally, I don’t care for the “my chest is about to explode” during my workouts.

  42. Coffee makes me feel calm in the mornings and like wonder woman during workouts. I would never stop drinking it- even if mark said to.

  43. my pre-workout prep involves a tablespoon of almond butter and a small piece of bittersweet chocolate. the caffeine from the chocolate is just enough of a spark to keep things rolling.

  44. Not a big coffee fan. One cup, black, warm — not scalding — in the morning. Done for the day.

    In the 80s I used to split a pot in the morning and also did several glasses of diet Pepsi {cringe} during the day. I started having PVCs that scared the carp out of me. Cut WAY back on the caffeine.

    I also didn’t like the way my insides started percolating after more than a cup or two. Not a good thing during a hard training run.

    I guess I wouldn’t do well in Seattle. Coffee during the day? YUUUUUCHHH!!!

  45. I still remember my best day of sparring class in my Taekwondo training days was when I had a double mocha right before class. My master instructor even commented on how much ass I kicked that day 😉

  46. Some interesting comments on the Demon Coffee.
    I have been an exercise enthusiast for many years now, it’s been a big part of my life. I did it because it is a great stress antidote, and I enjoyed it.
    Managed a couple of marathons, and Kayak Ultra marathons, weights, Mountain Biking, all good fun.
    Always ate and drank whatever I wanted, fried food, steaks, lots of fruit and vegies, plenty of whisky, wine, and COFFEE!
    Looking back, as I have just turned 70, I note that almost everything I’ve ever eaten, drank, or done- someone has been either for or against, at different times.
    My advise? If you enjoy it, coffee drinking or not, or any other dietary fad….do it. Probably won’t make much difference longterm anyway.

  47. anything wrong with taking a caffeine pill 200-400mg prior to working out? I don’t like the taste of coffee.

  48. coffee tastes terrible I have no problem with caffeine but what else is in coffee? If it is a super health beverage why does it make peoples breath smell like ass? and sweat smell worse?

    Its a product that you are meant to buy and become addicted to, and its an extremely thirsty crop , not very enviro friendly.

    1. Well since beauty is in the eye of the beholder, taste (good or bad) must be on the buds of the imbiber =)

      As for the smelly breath: I think most of us agree that garlic is a very healthy food (the russian penicillin, right?). I assure you that smell and health in this sense don’t have anything in common.

      What else is in coffee? Here’s a few:

      As a home roaster I can tell you that the amounts of the different compounds vary greatly depending on the origin/soil of the bean (well actually it’s a seed),your roast profile since they develop/diminish at different temperatures.
      Bonus fact: Coffees chemical composition is around 2,5 times more complex than red wine. -always a great kicker when battling hobbies with a wine connessieur 😉

      If you worry about the environment (as we all should) go for organic fair trade coffee -or even better direct trade. There are hundreds of great coffee farms to choose from in this category.

      1. Almost forgot:

        Most studies done on coffee and health point toward coffee consumed in moderation (generally 6 or less cups a day) have a beneficial effect on preventing Alzheimers, Parkinson disease (one study up to 75% reduced risk!) and diabetes.
        In addition, skin cancer risk may be reduced by caffeine and/or caffeine sodium benzoate (Study in progress).
        Lastly let’s not forget the antioxidants. Green tea may be the winner here, but coffee is on board as well.

  49. I’m not a coffee drinker, but I do have green tea. I notice that even that small hit of caffeine definitely improves my workouts! On the days I don’t have it pre-workout I notice I may be slightly more sluggish. And there is health benefits to green tea too so I’m just gonna keep on drinking it

  50. I prefer green tea. Especially the Japanese Sancha, or the Chinese Bancha.

    Combined with some dark choclate, it feels like heaven.

  51. What do you all think about caffeine tablets ? I bought some on spec because I can’t stand the taste of coffee (like the smell though). They’re 100mg per tab, I’ve been having one before the gym. Not sure if it is a placebo but I seem to be able to do more.

  52. Are you kidding me? Coffee doesn’t dehydrate? ya ok.. Everytime I drink it I urinate way more and feel dehydrated afterwords. I’m gonna have to disagree with pubmed. I’m sure I can find several sources on pubmed that supports that coffee dehydrates.

  53. Mark,
    Thanks for your great article. No surprise caffeine boosts mood and performance. But I wonder:
    1. How does caffeine affect long term health? Particularly cardiac health.
    2. How does caffeine affect our ability to maintain lean muscle mass and bone density, especially as we age?
    I’d love to hear your thoughts on this. Thanks again.

  54. Sometimes, when I drink a lot of coffee, my pee smells like coffee. That is when I know I have gone too far.

  55. Now my only concern is the side effects that pre work out drinks with nitric oxide have in comparison to coffee. If grok had NO ExPlode, white flood, jack3d, etc would he take it and then go maul a wildebeest?

  56. I love coffee- it truly helps with my workouts and gives me a fresh start to my morning.
    I will caveat however, that I gave it up several weeks again because it was severely aggravating my eczema, and interfering with my sleep. I will admit however, that my dosage was quite high. Moderating my coffee however, may yield different results. In the meantime, I’ve gone “cold turkey” so to speak, to eliminate my habitual need of 5-6 cups per day!

  57. I have a question that I haven’t seen addressed here yet : MY KIDS LOVE COFFEE! My 2 preteens (very athletic & eat mostly primal) both love coffee in the morning. I have always let them have a cup as long as they are eating healthy otherwise. I hear the old “It’ll stunt their growth” BS from people, but I don’t believe that caffeine or coffee can have a highly negative effect on really healthy athletic kids. Especially given what most kids eat these days, my kids having this one “questionable” indulgence doesn’t seem bad to me. They do not eat any processed food or drink soda, and eat primal at home & do pretty good selecting good foods when at a resatuant, school, or a friends house too. I am interested to see what you all think about this.

  58. Caffeine really helps give me more energy during my workouts. Howevr, every time I drink or eat something that has caffeine in it, I cannot eat for several hours after because it gives me acid reflux. Why does caffeine cause acid reflux in some people, but not in other people?

  59. I used to drink a lot of coffee, especially before P90X or Crossfit style workouts (nearly 2 years). Things went downhill; I found out I had low testosterone. Factors included little sleep, overtraining, and insufficient nutrition. Looking for a natural fix, eating primal came first, then, more sleep. I started training less, but my cortisol still felt like it was through the roof(1 year). After quitting coffee and cutting training way down, I FINALLY noticed improvement in a couple months time.

  60. Mark,

    This is a good post. Interesting pint about the instability of coffee depending on soil, place of origin, etc. I am type 1 diabetic, so I generally have to keep a very close beat on my endocrine system. I find that when I drink most mass produced, commercial coffee (especially Folgers), my Insulin sensitivity plummets and I require a lot more. Obviously, this is undesirable. I figure there must be some compound present in the coffee that I responsible. I switched to organic coffee, and everything returned to normal.

  61. I definitely consume my fair share of caffeine as I drink a cup of coffee in the (very early) morning then try to get 2 cups of tea later on the day. But before exercise I try to avoid it. Tends to make me jittery.

    “Studies on cognitive performance and caffeine have found that when you account for the withdrawal effect, caffeine has little to no benefit to performance.” That’s an interesting point and would love to see more as it relates to athletic performance.

  62. Someone once suggested that my unstoppable coffee habit is actually self-medication for my blood pressure. Last time I had it taken, the corpsman asked me if I have ever been diagnosed with low blood pressure: I had no caffeine and had fasted for a blood sugar test, and my blood pressure was a dead-on 90/60.

    Maybe that explains why it takes A LOT to make me jittery. One cup in the morning starts my day off right, and one cup early in the afternoon just makes me cheerful. Literally just plain happy.

    No sleep problems for me, nor any real workout benefits.

    1. If I had read your comment years ago, I would have totally related. I tend toward low blood pressure myself. I’m starting to wonder, though, about the relationship between caffeine and blood pressure.

      Until my first pregnancy in my mid 20’s, a reading of 90/60 would not be at all unusual. I finally had my first “normal” blood pressure readings – around 110/70 – during the second trimester.

      Now, at age 59, I still have good blood pressure – 115/75 (pre-primal) – despite being over weight and having other markers for metabolic syndrome. I also tend to have a low resting heart rate, even after a cup of coffee.

      That said, I have also developed sensitivity to caffeine. It disrupts my sleep, even one cup early in the AM. One time I drank several cups throughout the day just to see what would happen. I got hyper and edgy – plus the expected insomnia. Not much of an effect on blood pressure, though.

      Now, after several weeks eating 100% primal and only drinking decaf, my blood pressure is looking more like it did in my 20’s. Average 105/65. And, I am still sensitive to caffeine in terms of insomnia.

  63. Relatedly, I had always heard that coffee and tea leach vitamins & nutrients out of your system, so you shouldn’t drink them near the time you eat (or take supplements).

    Has anyone heard/read anything to support or contradict this?

  64. THumbs Up! I love coffee,it boost my strenght during workouts and i can’t sleep like a baby without it period!!!

  65. Coffee is what keeps me alive in the afternoon between lunchtime and heading to the gym.

  66. I absolutely love my coffee! I’m just wondering what your thoughts are on it causing the body to store fat? I keep hearing how I need to cut out coffee because it spikes your insulin causing you to store more body fat. Any thoughts? Thanks so much!

  67. I’ve been drinking tea and coffee during workouts for years, and with positive results. No dehydration. Better performance.

  68. In her book Primal Mind Primal Body, which, lets be honest is the best researched primal book there is (perhaps not the most livable) Nora D is emphatic that coffee is an all out poison. Adrenals suffer, pancreas suffers along with a whole host of other not nice stuff.
    I loved coffee for 4 years and then just started to feel it wasn’t doing me good. After the extraordinary detox headaches I’m free and all is good without.
    I think a combo of personal awareness, Norah’s book and the latte factor, ended my love affair with it.

  69. there is a ton of science on both sides. I think the key with this is the same with any substance that is potentially addictive and a stimulant.

    Pay attention to your body, recognize the things that historically have been negatively associated with Caffeine (high blood pressure/TC, jitters, sleeplesness, etc), and be willing to adjust our habits as necessary.

    I love coffee (live in Seattle AND worked for Starbucks in the early days when a barista really had to make the drink). but lately (especially after going Paleo), I’ve had to be more reserved about my consumption. After a week of almost no sleep, i started to cut back on the coffee…and my sleep improved dramatically.

    I think that we have to remind ourselves that we are a holistic creature…not a group of science articles all thrown together in a mess. we have to use science as what it is…a tool, and listen to what our bodies are telling us. My body told me that it was time to cut back 🙂 not everyone will have to do that, but as long as your listening to yourself, you’ll probably be fine.

  70. For me, caffeine is dehydrating based on how diluted it is. I assume that’s fairly universal.

  71. I’m a 67 yr. old male, that has been drinking coffee most of my life,and I mean lots of coffee.I did suffer from High Blood Pressure & Border line Diabetes for over 20 yrs. This I and my doctors agree was hereditary.I was taking meds for the pressure problem and just monitoring my sugar,pricking my fingers 2 times a day”OUCH”. I’m 5’8″ and was about 20-30 Lbs.over weight.I lost the weight and started working out,eating semi-healthy,but still drinking lots off coffee. By loosing the weight,working out and getting my BMI (Body Mass Index) where it should be
    my doctors took me off the meds and I don’t prick my fingers anymore. Coffee has always given me a boost all day long. It gives me a boost in the morning when I’m at the gym and everybody is telling me that I shouldn’t be drinking it because I drink it at the gym. It has always worked for “Me”. Now all I take is my Vitamins, A baby aspirin and lots of coffee and I’m in tip-top shape. Thank you for Verifying Coffee is Good “FOR ME”

  72. I used to be a coffee addict. But over the years of working to improve my diet, I finally had to come to the conclusion that coffee was just too toxic and dehydrating. I mean, it’s a bean or seed, and nature puts all sorts of insecticides and toxic chemicals in it to protect the seed. I heard somewhere that a coffee bean has about a thousand toxic chemicals in it, naturally.

    Whether it actually does technically ‘dehydrate’ the body or not, I’ve found that its toxicity necessitates that I drink massive amounts of water to overcome its ill effects. If I have just one cup of coffee during the day, I can count on having to wake up every hour during the night to drink water, or else suffer from headache and relentless thirst.

    In my primal low-toxin diet, coffee just doesn’t fit, and nowadays I only indulge once every few months or so. And then predictably suffer all night because of it, not from the caffeine, but from the physical imperative to flush out all those astringent toxins with copious amounts of water.