Dear Mark: Decline in Mental Energy

FatiguedDear Mark,

Have you noticed a decline in mental energy or focus since not doing “cardio”? I have read several reports that indicate that aerobic exercise is best for mental performance. Any thoughts?

Thanks to reader Phillip for his question on the comment boards. I’ve talked a lot over the course of the last few months about chronic cardio and the very real disadvantages of this type of training (higher cortisol levels, oxidative damage, systemic inflammation, depressed immune system and decreased fat metabolism, etc.). However, just because I don’t do chronic cardio anymore doesn’t mean I don’t get huge cardio benefits from the high intensity sprints and other interval exercises I do. This high intensity part of my workout is short compared with the hours I used to used to spend training. I choose to consider efficiency as a factor in my training program, and (as I’ve said on a number of occasions) I’ve never felt better than I do now.

Personally, I haven’t felt any decline in mental energy or focus since I dropped out of the chronic cardio race. I used to feel like napping mid-afternoon, but these days I’ve found that my energy levels are more even throughout the day. A big part of that, I’m sure, is not experiencing the rundown and recovery phases. Because I now skip the extra cardio, I have more energy and more time for the other important and healthy things in my life. I feel a lot less stressed physiologically and psychologically because of the changes I’ve made to my routine.

There are a slew of studies out there that confirm the benefits of exercise for mental clarity, concentration, stress, anxiety, you name it. Rigorous exercise (before you get to the law of diminishing returns) stimulates the central nervous system and the activity of neurotransmitters like serotonin, which enhances mental clarity and focus. But it doesn’t need to be traditional cardio of long duration. In fact, if your routine gets the blood pumping and healthily stresses the heart, you’re getting cardio benefits (and all the other associated advantages like improved mental clarity). I’m not familiar with any study that specifically compares the impact of interval training with traditional cardio on mental clarity/function/fatigue. I’d love to see them if there are any floating around out there.

When it comes to mental as well as physical function, the Primal Blueprint works with our primal design. The exercise model is meant to healthily stress the body without exhausting it. When we perform any kind of rigorous exercise that doesn’t exceed, say, 45 minutes or so, we never deplete our glycogen store to the point of descending into muscle breakdown, and we never starve the brain as we can when we train hours a day.

As always, thanks for your questions!

Graham Binns Flickr Photo (CC)

Further Reading:

More Chronic Cardio Talk

Dear Mark: Weightlifting Weary

The 7 Habits of Thin (Healthy) People

Subscribe to Mark’s Daily Apple feeds

Sponsor note:
This post was brought to you by the Damage Control Master Formula, independently proven as the most comprehensive high-potency antioxidant multivitamin available anywhere. With the highest antioxidant per dollar value and a complete anti-aging, stress, and cognition profile, the Master Formula is truly the only multivitamin supplement you will ever need. Toss out the drawers full of dozens of different supplements with questionable potency and efficacy and experience the proven Damage Control difference!

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.

If you'd like to add an avatar to all of your comments click here!

6 thoughts on “Dear Mark: Decline in Mental Energy”

Leave a Reply

Your email address will not be published. Required fields are marked *

  1. Since I switched to a high intensity exercise modality 2 years ago my standing heart rate dropped from low 70’s to mid to upper 50’s and I don’t do any low intensity cardio work. I also probably lowered my stress levels by not worrying about scheduling in the hour or so (3-4 days/wk) I used to need for my workout.

  2. They say the best workouts leave you feeling great afterwards, and I find that to be true. Unless one is severely overtraining, mental energy should remain high. That lots of good quality fats in the diet also help!

  3. I’d wager my left nad you won’t go wrong(i.e getting the aerobic benefits and being devoid of excessive thinking, feeling energized and basically just feeling grand to be alive) with oodles of walking and some brief intense weight work outs..whether chucking tyres around, doing some Turkish get-ups, just a bit o variety, randomnly performed, not being rampantly obsessed with having very low body fat (i actually think rightly or wrongly that the obsessiveness that some lads(and lasses) have about low body fat is likely a symptom OF low body fat and a kind of obsessive-compulsive disorder whereby the body is stressed to the nines and the lower fat ‘tells’ the body it’s using too much of its reserves, thus elevates its stress profile which manifests in this obsesiveness about fat amount on the body as when stressed it doesnt make an informed choice about upping fat.From reading articles and blogs etc that most folks who have low b-f are assuredly not like Senor Mark who eats a high fat diet.I’ve noticed with myself and others that if i take in enough fats i could sit in a vat of choccy and not be tempted but reduce my fat cals and of course ones brain/system wants cals and its manifests that need via cals that are quick….carbs or sugar.Also a pal who on and off has drink binges seems to have found that if he eats more fat he reduces it’s cravings.
    If the observation has any merit it might be as cos plenty of fatty is coming in the body ‘feels’ it’s okay to dip into its reserves and also isn’t stressed as in a evol sense it’knows’ it’ll survive as its getting oodles of cals too.

    All that might be poorly worded but hope you get the drift / the actress said to the bishop !

  4. Thanks Mark
    I new there had to be a better way than tearing your joints up through excessive cardio.

  5. Thanks Mark for addressing the question. I agree.

    The biggest adjustment I have faced has been volume of exercise. As a runner, I bought into the more is better theory. When I switched to kettlebells and intervals, I tried to do too much. Inevitable burnout ensued.

    I was quick to blame the type of exercise for decreased mental and energy levels. However, once the volume was reduced, I was feeling better than I had when running. I certainly appreciate your thoughtful insight into chronic cardio and primal fitness.