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Let me introduce myself. My name is Mark Sisson. I’m 63 years young. I live and work in Malibu, California. In a past life I was a professional marathoner and triathlete. Now my life goal is to help 100 million people get healthy. I started this blog in 2006 to empower people to take full responsibility for their own health and enjoyment of life by investigating, discussing, and critically rethinking everything we’ve assumed to be true about health and wellness...

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March 23, 2016

Should You Sleep-Low to Boost Performance?

By Mark Sisson
59 Comments

Should You Sleep-Low to Boost Performance FinalThought experiment time. Say you train hard, hard enough to deplete a signifiant amount of glycogen. Your muscles are empty, sensitive to the effects of insulin, and screaming for a couple potatoes to refill glycogen. What do you do?

In most circles, the answer is to eat those potatoes and refill those glycogen stores. And why not? The post-workout period is a special window of opportunity for eating a bunch of carbs and having them go to the right places with minimal insulin required. They won’t contribute to fat storage. They’ll go straight to your muscles. Restocking glycogen sets your muscles up to repeat the hard work and keep up with your training. It makes sense.

What if you didn’t eat the potatoes after a hard workout? What if you abstained from carbs entirely after a glycogen-depleting workout? What if you just went to bed without any (carbs in your) supper? What if you were an elite athlete and skipped the carbs?

That’s exactly what a team of French researchers had a group of highly trained male triathletes do, according to a study released a couple months back.

They were exploring the effects of a “sleep-low” eating regimen on the type of performance indices relevant to endurance athletes. It was a really interesting study.

First of all, everyone was highly-trained. These were elite triathletes, the cream of the crop. No weekend warriors in sight. They were split into two groups: a control group and a “sleep-low” group. After a three week induction period of identical diets, supplements, and training, the experimental phase commenced. Both groups ate the same total amount of carbohydrate (6 g/kg bodyweight) each day, just at different times. The control group ate theirs with every meal. The sleep-low group ate theirs at breakfast and lunch.

Training was identical for both groups. For four days straight each week, both would follow a routine.

In the afternoon, they’d perform high intensity training sessions, either 8×5 minutes cycling at 85% maximal aerobic power output (MAP) or 6×5 minutes running at 85% MAP (alternating each day) with a minute between each interval.

In the morning, they’d do low intensity aerobic (LIT) work before breakfast: an hour of cycling at 65% MAP.

The sleep-low group ate carbs at breakfast, lunch, and a pre-workout snack. Then a HIT workout. No carbs until breakfast the next day after the LIT session.

The control group ate carbs at breakfast, lunch, post-workout, and dinner. Breakfast came after the LIT session.

After three weeks, the scientists subjected both groups to submaximal (LIT) and supramaximal (HIT) cycling performance tests, Vo2max tests, and a 10k run (to simulate the final leg of a triathlon). The sleep-low group performed these tests in a “low-carb availability” state (low glycogen). The control group performed them in a carb-replete state.

What happened?

Submaximal efficiency (power output per calorie burned when pedaling at moderate intensity) greatly improved in the sleep-low group. The control group saw very little improvement. This is a crucial biomarker for endurance athletes. If your submaximal efficiency is high, you get more power out of each stride/pedal/stroke with less energy required. That means your “easy pace” is faster than the other runners.

The sleep-low group’s supramaximal capacity also saw a major boost. They were able to cycle at 150% of their Vo2max for around 12-20% longer than before. There was very little improvement in the control group.

In a 10k run test, the sleep-low group shaved around 3-5% off their times. The control group shaved just 0.10% off.

Even though they were all quite lean to begin with and this wasn’t the purpose of the study, the sleep-low group lost more body fat.

This was the “have your cake and eat it too so just long as it’s not at dinner” study. When they did HIT, they were glycogen-replete and dominant. When they did LIT, they were running on fat and just as dominant. They weren’t on a keto diet. They rapidly reached the very-low carb/ketogenic state for a good portion of the day by depleting glycogen and failing to replace it, from the afternoon snack to the post-workout breakfast. They weren’t just “high-carb.” They were smart carb, filling the glycogen, depleting it, and forcing their bodies to run on fat for a while.

What’s truly remarkable is that this was a short-term study. Three weeks of experimental conditions were plenty for the benefits to accrue and amass. They didn’t have to spend six months getting adapted. They didn’t go through a keto induction period. They manipulated the pattern of energy substrate use through carb and workout timing. This is simple stuff anyone could do. And if the elite athletes (triathlons are no joke!) can benefit from it, I’m pretty sure the average person trying to improve performance will see benefits.

Another cool part is that even though the sleep-low group performed HIT workouts in the carb-fed state throughout the study, they were tested in a carb-depleted state and still saw huge improvements. They “trained low, raced low” when it came to submaximal endurance and “trained high, raced low” when it came to supramaximal capacity—and both modalities improved. That’s huge.

What’s going on is forced adaptation. By waiting to eat more carbs immediately after you deplete yours, your body has to upregulate fat metabolism. You will get the carbs soon enough—you’re going to eat them the next day after your morning workout—but you make your body wait a bit. In the meantime, it has to work with what it has available: fat. This study is just the latest to show that forcing these adaptations can have real benefits.

If you wanted to try this out yourself, you could follow the schedule in the study. You’d have to have a lot of free time and flexibility, but it’d probably work.

If you’re a normal person with a normal schedule, you could do a truncated version. Eat carbs before your high intensity workouts and none after. Go for a walk or a light jog in the morning before breakfast. Eat carbs with breakfast and lunch and perhaps a snack before your high intensity workout. You probably don’t need the 6 grams of carbs per kg of bodyweight the athletes ate in this study. Whatever you do, be sure to really deplete glycogen and wait for 12-16 hours to refill it.

Standard low-carb dieting promotes similar adaptations, but it works more slowly. Glycogen depletion takes a while if you aren’t training intensely, so you can speed up the process by throwing in some sprint, circuit, or HIIT workouts.

I know from personal experience that this can work (hence Primal Endurance). Once or twice a week, I like to fast after workouts. That’s a slightly more extreme version of post-workout carb abstention, but it’s the same idea: withholding food and forcing your body to adapt. This increases growth hormone (important for fat burning and cellular repair) and speeds up fat adaptation.

So, who’s interested in trying this out? Anyone? Let me know how it goes in the comment section!

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59 Comments on "Should You Sleep-Low to Boost Performance?"

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CharlesQj
CharlesQj
6 months 3 days ago

Yet another supporting example of conventional wisdom, when eschewed in another setting, biting the dust.

Rachel
6 months 2 days ago

The research into this is actually a lot less definitive than you might think, and it’s more important to get enough carbs over the course of the whole day, rather than worrying about squeezing them into the post-workout window. The idea that you should only eat carbs right after a workout is just unnecessarily restrictive: exercise increases insulin sensitivity for up to 48 hours after you hit the gym, so there’s no magical 30-minute window to cram in your carbs for the day.

Michelle
Michelle
6 months 3 days ago

Endurance athletes try this at your peril. Everyone is different, and there are certainly benefits to a ketogenic lifestyle. But for many it absolutely destroys performance within a relatively short period of time. And any regimen where you struggle to continually supplement with nutrients you should be routinely receiving through your diet bears questioning. Experimenting with diet and performance is generally worth a try, but I have not found many/any endurance athletes who have made it work for more than a relatively short period of time. Eating for optimum health is the best performance boost there is.

Cari
6 months 3 days ago

That’s precisely why this strategy could be a good alternative for those who are not wanting to go low-carb. If you didn’t notice, all of these athletes are eating an overall extremely high carb diet in terms of “primal” standards.

John Es
John Es
6 months 3 days ago

But, thank God for those who *do* try things at their own peril.

Jay
Jay
6 months 3 days ago

I’m not sure are correctly interpreting this article. Its not about persistent ketosis, or even about carb restriction. Its about nutrient timing and adaptive responses that do boost both performance and health markers.

Colin
6 months 1 day ago

I agree Jay. Daily carb intake was the same for both groups. The structure of no carb at dinner to create extended ‘adaptive’ period followed by low intensity morning session seems to be well thought out. I’d be interested to see the outcome if breakfast was the no carb meal.

Tony
Tony
6 months 2 days ago
I hope this doesn’t come across more confrontational than I intend. My assumption will be that those of us who visit Mark’s site, and others with similar goals, do so trying to further our knowledge and perfect our own eating and health goals. Anyway: -Zach Bitter (http://zachbitter.com/accomplishments.php) current record holder for 100 miles on a track and distance run in a 12 hour period among other accomplishments. -Sami Inkinen (Wold Class tri-athlete) and Wife Meredith row 4000 kilometers from California to Hawaii unsupported. The record for a 4 person team was 60 days. The accomplished the feat in 45 days… Read more »
Mike
Mike
6 months 19 hours ago
Not to be rude, but I disagree entirely with your statement on supplementation. If you honestly think you’re going to get every nutrient, from vitamins and minerals to whatever other trace metals etc, from your diet of green leafy vegetables, protein sources and fats, you are wrong as the day is long. I doubt you could find any paper/study on nutritional values from today’s time where it lists amounts of vitamins and mineral content. It will most likely be 50yrs or more old. You are what you eat, and so is that vegetable. So unless you’re growing your own garden… Read more »
Pam
Pam
6 months 3 days ago

So, what if I workout in the early a.m. before breakfast? Would I then eat my carbs for lunch and dinner or still breakfast and lunch? I usually don’t eat anything until about 10 am.

Kalen
Kalen
6 months 3 days ago

“Whatever you do, be sure to really deplete glycogen and wait for 12-16 hours to refill it.”

How do you know when you’ve depleted your glycogen?

Susan
Susan
6 months 3 days ago

Same question above. What if I workout in AM?

Sam
Sam
6 months 3 days ago

Ditto on that question as well. When I work out it is usually between 6 and 7 a.m. I guess I could just do a keto-like day after a hard workout, and then refill carbs the next day?

Vo2Max
4 months 14 days ago

Easy answer… Don’t work out in the AM. 😀

Jennifer
Jennifer
6 months 3 days ago

Was this study done on all male athletes? I am curious as to whether it would be the same for both male & female athletes….

Margaret
Margaret
6 months 2 days ago

The abstract doesn’t state whether they were male (a huge blind spot for researchers), and the New York Times article on this doesn’t say either. But I think I can guess …

Carly
Carly
6 months 2 days ago

He says in the article it was all make athletes. Just from anecdotal evidence, here and otherwise, women of childbearing age don’t seem to do as we with intermittent fasting/keto/very low carb, so I’m doubtful it would have found the same benefits for women. You could always make yourself the experiment though and try it!

Ron Pereira
6 months 3 days ago

The one thing I’m curious (haven’t read full study) is whether the low carb folks slept OK. Carbs at dinner seem to really help my serotonin levels which then seems to promote better sleep.

Nocona
Nocona
6 months 3 days ago

Yes, this is my question too! I have started fasting before and after my morning workout to boost growth hormone and have no problems doing that, but if I don’t eat some carbs with dinner then my sleep suffers a bit. I need carbs at night.

Erik
Erik
6 months 2 days ago

Are you sure it’s the carbs or could it be the fiber? I’ve heard that fiber actually can be helpful in promoting restful sleep and too many carbohydrates can actually be detrimental to sleep just like too much protein or too much fat before bed, though for a different reason than the latter two.

Paleo Lady
Paleo Lady
6 months 3 days ago

That’s my concern as well. If I’m even a little hungry I can’t fall asleep, and if dinner isn’t late or substantial enough, I wake after a few hours. Insomnia is no joke, so if I ever fast, it is from waking to about 4:00pm, and whatever exercise I can manage is usually in that window.

But then I’m an old lady with a bunch of autoimmune disorders, so today’s article probably doesn’t apply anyway 🙂

ML
ML
6 months 2 days ago

If you haven’t already, try drinking chamomile tea before bed. I have the same sleep issues, but the tea (I use Trader Joe’s brand) knocks me out and keeps me sleeping through the night.

Eva
Eva
6 months 2 days ago

I don’t sleep well without magnesium supps, i need 400 mg per day with the supps, my body apparently had high demand for magnesium. It’s my only medication other than DMSO on the skin for tendonitis (caused by sports which I like too much to stop). Magnesium is the magical sleep supplemetn!
-Eva

Stevie G UK
Stevie G UK
6 months 2 days ago

I hear you Paleo Lady, I have the samne issue(s) though I’m male. Can’t sleep at all if not eaten an hour or so before bed.

Lew
Lew
5 months 28 days ago

I have had the same issue. I did the 21 day challenge, and about the beginning of week 3, I started to wake at 2 or 3am. I continued with a second 21 day challenge with Bee the Wellness and Vanessa suggested that I have sweet potatoes with my evening meal. Once I did that, I slept great. I was pretty low carb diring the challenges. She thought it was my liver going into glucenogenysis mode. I slept great after that.

Tara
Tara
6 months 3 days ago
I tried something like this accidentally a while back. I was eating pretty low carb, and I added HIIT three days a week for about twenty minutes. I was completely exhausted for the whole evening– as in like a slug, all I wanted to do was lay on the couch, and as a relatively active person at a healthy weight, that wasn’t normal for me. That only lasted about 3 weeks until I figured out adding carbs after helped the lethargy. I wonder if the test subjects experienced that or not. Anyway, I might give something like this a try… Read more »
David
David
5 months 30 days ago

I agree with Tara. Eating starchy carbs after a workout, keeps me from feeling lethargic. Learned the hard way. Even eating starchy carbs (small amount) helps too. My body fat levels always remain the same as long as I am eating Primal :).

Jessica
Jessica
6 months 3 days ago

My mom has been doing this by accident for about 3 months and has lost 20 lbs! She told me she goes dancing after work (which I think is high intensity for her) and just has a protein shake or nothing for dinner. Now there’s scientific evidence to back up her method!

Erica
6 months 3 days ago

I’ve been following a carb cycling and intermittent fasting program for a few weeks with great results. I’m definitely going to tweak the timing of my workouts to take advantage of depleted glycogen stores.

Mycroft Jones
Mycroft Jones
6 months 3 days ago

Carey Reams was teaching this decades ago: big carbs for breakfast and lunch, light salad and maybe some meat for supper. He was helping people recover from cancer.

Paul Mitchell
Paul Mitchell
6 months 3 days ago
Erik
Erik
6 months 2 days ago

Except it’s not the same thing. In fact it’s the complete opposite. They weren’t fasting at any point outside of sleep. Instead they were basically front loading their carbs in the morning and afternoon and only consuming fats and proteins in the evenings.

At best you could claim it is similar to an evening fast into sleep but few people practice that way and favor either a sleep into morning fast or all day fasts. Plus those would be true fasts with no significant calories. This was not that, this was only limiting carbohydrates for a certain period.

HealthyHombre
HealthyHombre
6 months 3 days ago

So eat carbs like a king for breakfast, like a prince for lunch, and like a pauper for dinner? 🙂

Valerie
Valerie
6 months 1 day ago

For those of us dealing with Adrenal Fatigue, the opposite is true. Lower carbs at breakfast and lunch and then majority of carbs with dinner. All meals having protein and fat and fiber as well. Too much protein at night can raise cortisol which can cause insomnia. Highest cortisol levels should be in the morning. Carbs at night are conducive to better sleep.

Whitney Treadwell
Whitney Treadwell
6 months 3 days ago

I have been holding off eating after a workout, especially HIT, but to enjoy the lingering hormonal uptic in hgh and testosterone. Hadn’t thought about the fat adaption benefit.

Becky D
6 months 3 days ago
Interesting article. I have been experimenting around staying in ketosis before and after workouts purely because I hate packing lunch and like working out mid-day. I have a keto shake for breakfast, skip lunch, do strength training or HIIT in the early afternoon, then eat in the evening. Often it’s pretty low carb: veggies, nuts, meat, cheese though sometimes I’ll have a starchier veggie or some fruit. I was super nervous about trying this, but it was so convenient and worked out great for me. I hate having to figure out what’s in the fridge for lunch every day and… Read more »
Paleo Lady
Paleo Lady
6 months 3 days ago

Great idea! Only thing more annoying than packing lunch is eating in my office, doing dishes…bleh. That’s really interesting about the milk. Thanks for sharing.

Christopher
6 months 3 days ago

“Both groups ate the same total amount of carbohydrate (6 g/kg bodyweight) each day, just at different times. The control group ate theirs with every meal. The sleep-low group ate theirs at breakfast and lunch.”….

This certainly fits with the premise that paleolithic man eating what’s at hand, first thing in the morning… and then go hunting.

Kim
Kim
6 months 3 days ago

Argh, I think this is almost the opposite of what I thought I just heard on a Sisson/Greenfield podcast. The just of that was better body composition moving all carbs to nighttime, that appealed to me for the reason of sleep that others have mentioned!

Brian
Brian
6 months 2 days ago
So basically: Morning = Carbs, yes Please! Lunch before intense workout = Carbs, damn straight! After Workout = What are carbs? Never heard of these things called “carbs” Fuel to train, but I suppose it depends on what the person’s goals are. If your goal is either strength, performance, size/gains or anything of the like, you have to eat, there is no if’s, and’s, or but’s about this. This would include probably having square meals all throughout the day. If your goal is maintenance or fat loss, maybe this is the way to go. Either way Grok didn’t go out… Read more »
LMT
LMT
6 months 2 days ago

I wish I could implement this, but my problem is that a) if I don’t work out first thing in the morning, I won’t work out at all, and b) if I have to eat at one time during the day, it has to be at dinner time as I can’t sleep when I am hungry.

Catherine
Catherine
6 months 2 days ago

I teach spin 8 am 4 times a week which is big time HIIT I then do the LIT in the evening. (training for Ironman) Sometimes I swim (LIT) after the HIIT or do the Max sustained power sets (2-3 times a week). So this is my experiment. No carbs until 6-8pm 10-12 hours after the HIIT with my dinner. At lunch (I don’t eat breakfast) with protein only. I might have to add a protein shake after HIIT to keep going. Humm… sounds weird. But I will report back.

Mr Nofish
Mr Nofish
6 months 2 days ago
Out of curiosity I looked up MAP, since I could not recall what relationship it had to FTP, but did remember Alex Simmons using MAP and indeed he has handy tables detailing the zones. 65% MAP is actually high tempo, looks about comparable to Sweet Spot to me, while 85% MAP is the higher band of threshold or TT pace. Now this shouldn’t probably surprise anyone given that they’re elite (those 1 minute long “recovery phases” are kind of a dead giveaway…), however if you’re reading the post and picking up “low intensity” and “high intensity” as general concepts, you… Read more »
Alessandro
Alessandro
6 months 2 days ago
This is very interesting as it goes against what I thought was the holy grail of carb partitioning, namely eating the bulk of them at night (in my case with breakfast skipping IF)! I usually do some fasted easy cardio and mobility before lunch and then a strength training session in the evening, so I would just have to squeeze all my carbs into lunch and afternoon snack and then have protein, fat and green veggies for dinner which would be no problem 🙂 Now this study looked specifically at endurance training while my goals are strength and physique. The… Read more »
Jack Lea Mason
Jack Lea Mason
6 months 2 days ago

This study is biased towards maximum performance athletes. If one is overweight and struggling to be active, this is out of their league. The overweight should limit carbs all day until they can achieve something like an unassisted pull-up, run an 8 minute mile, and hold al plank for 2 minutes. If one is competing as a triathlete, carb timing may be necessary for peak performance. This doesn’t apply for those of us that hope to someday complete a triathlon, rather than win one.

MassageTeam
6 months 1 day ago
Not trying to sound too snarky here but… “Unassisted pull up” is a man’s benchmark. The vast majority of women will never be able to do an unassisted pull up and that doesn’t mean that they are out of shape or unhealthy. I have amazing bone density and I am generally a very ‘heavy on the scale’ person. My entire life, – not even as a girl – have I been able to do a single unassisted pull up, rope climb, you name it. That said, my metabolic engine is awesome for my age and gender. Noticeable body composition improvements… Read more »
Jack Lea Mason
Jack Lea Mason
6 months 1 day ago

Please forgive my insensitivity. In my defense I know several women that can do more pull-ups than me. One is five years my senior. My point was carb tuning is for competitive athletes not for the majority of us that simply don’t want to feel embarrassed in a swimsuit.

MassageTeam
6 months 1 day ago

Thanks. I’ve seen those gals at my Crossift gym also. They are all ages teens – early 30s max, in the “firebreather” category. The rest of us females look on with our jaws dropped. Fun to watch, unrealistic to emulate.

I get the “look good naked” drive. If I ever get there, I might also be able to do a pullup with a less beefy band to accomplish the trick than is currently required. Fingers crossed.

Jamie
Jamie
6 months 2 days ago

No surprise to me. I’ve been doing the Sprint 8 HIIT workout for over a year now. The guy that invented it sais you should eat at least 20g protein directly after the workout and hold out on carbs as long as possible.

The idea is that this boosts the post workout Human Growtrh Hormone from this type of HIIT.

So carbs would immediately stop the surge of HGH.

Ann Coleman
Ann Coleman
6 months 2 days ago
Wow. This is what keeps me coming back here! Thanks, Mark. You answered a question I didn’t even know to ask! I have bit of info re: a low intensity (kind of accidental) version of this regimen and it’s effect on a post-menopausal, not-particularly-fit, 65 year old lady. Eight years ago, I was 100 lbs overweight, and completely out of shape, but otherwise healthy. Since getting serious about my health, I’ve lost 100 lbs and my fitness level has been steadily improving, but we are not talking elite athletics here! I follow a primal eating plan (about 70/30) with no… Read more »
Caroline
Caroline
6 months 1 day ago

This is amazing, Ann, how lovely to hear of your transformation into The Beast!

Gabriel Rücker
Gabriel Rücker
6 months 2 days ago

So, if i’m doing PBF this is not needed right? Because the workout doesn’t require too much glycogen to get through it

Erik
Erik
6 months 2 days ago

I wonder how this would do for a type 2 diabetic?

Quinto
Quinto
6 months 2 days ago

“When they did HIT, they were glycogen-replete and dominant. When they did LIT, they were running on fat and just as dominant.”

What does dominant mean in this context?

Brandon
Brandon
6 months 1 day ago

Does this still apply to the more traditional full-body strength workout? I would love to try if so. My carbs have been in the 200-250g range but I’m doing three strength workouts, a sprint workout, and the other days are pretty active playing sports or hiking with my 3 year old. Thanks!

MassageTeam
6 months 1 day ago
Judging by most of the comments so far people are really missing a key point about the carb timing. The big takeaway of the article was NOT that we now need to flip on its head the idea of when was the best time of day to have carbs (morning versus evening). The big takeaway was to forget about that 30 – 60 Minute refill carbohydrate window post-workout and instead stretch it out to a 8-12-hour window, by my estimate. In other words if you do a MORNING HIT workout, stick to proteins and fats the rest of the day… Read more »
Rick
Rick
6 months 1 day ago

Maybe there is little more to all this than simply going without carbs for 12-14 hours a day. Possibly one should spread their reasonable quantity of carbs out fairly evenly during the carb-eating period.

Anyway, I’ve been trying basically what the article suggests, carbs at breakfast, tiny carbs at snack, carbs at lunch, tiny carbs at snack (totaling 100-120 gm), then a hard workout, then no carbs at dinner and none until breakfast. Last night, at 0200, zing! Wide awake. I am now going to try tiny carbs after dinner, for sleep purposes, and moderate carbs at breakfast.

Monika
Monika
5 months 29 days ago

I’d like to ask a question here, because I don’t know where else to post it.
I know I’m not the brightest bulb, just don’t have the education.
After reading Mark’s Primal Endurance (for interest, never have been, nor will I be an Endurance Athlete) I don’t understand the difference between chronic cardio, and the training Endurance Athletes do on a daily basis, for hours, and hours, be it running, biking, swimming etc. Why is that not chronic cardio?
Thanks in advance for your illumination!

Ciaran
5 months 25 days ago

Where does gluconeogenesis (GNG) fit in with this? If you eat protein after a workout, won’t your body convert some of the protein into glucose (using GNG) and restock your glycogen that way? And what drives GNG in any case? How does your body decide how much protein to convert to glucose? Is it strictly driven by a glycogen shortfall, or will GNG ‘keep going’ and produce ‘surplus’ glucose? Or does muscle repair take priority over all this in how proteins are used? (6 questions there. Sorry about that, folks. Answers to any one of them would be appreciated though)

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