This article takes you through the world of Exercise Dynamics and how your body reacts to being under consistent physical stress. A study published in 2012 [1], compared daily energy expenditure and body fat between "The Hadza hunter-gatherers from northern Tanzania" and individuals in "western populations". An astonishing result that came from the study was that:
Hadza hunter-gatherers and westerners had similar total energy expenditure despite the dramatic differences in their lifestyle.
While The Hadza population hunts for food by walking daily for long periods of time without any help from modern equipments, and over 95% of their daily calories come from wild tubers, berries, and honey, the western population in market economies has a comparatively sedentary lifestyle with highly processed, sugar-rich diets. How can the energy expenditure for the day be similar in these two populations? Does this mean westerners are just as physically fit as Hunter-Gatherers in Northern Tanzania? It seems we can burn as many calories as any other hard-working hunt-gatherer just by sticking to our western lifestyle with little to no movement. Why go to the gym then? Wait. Let us first look at another study from 2016 [2], which proposed a constrained total energy expenditure model in adult humans suggesting that,
The human body adapts to physical activity after a certain peak is reached. Therefore, our total energy expenditure for a specified time period plateaus.
This means that our body compensates for increased physical stress by reducing the work done in other internal body functions such as hormone production, metabolism, immunity and inflammation. Put in extremely simplified terms, while a gym goer uses his/her energy expenditure quota for the day to build muscle, a gym non-goer uses the same energy for metabolic processes. This can be seen by examples like - low basal metabolic rate in individuals enrolled in long-term exercise [3] and suppressed ovarian activity along with low estrogen levels in women who engage in consistent physical activity [4]. People not undergoing hefty amounts of physical stress on a daily basis have a metabolic surplus, which their body uses for processes that are otherwise not really required in such great amounts. Moreover, the excessive visceral adipose fat in such individuals has been proven to be a significant trigger of chronic inflammation, which further contributes towards accelerated aging, cardiometabolic diseases, and even several types of cancer [5].
This basically means that your body is a well-oiled machine with various parts working at a synchronized pace and the Surplus Metabolic Energy is a superpower given to your immune system and metabolism to short circuit the system.
Courtesy of kurzgesagt.org
The above discussion makes it clear that our body wants to be in a balanced Zen mode at all times. We essentially have to find a way to trick our bodies into thinking it's still in Zen even when under physical stress. A balance of physical activity and calorie intake helps ensure that. We at Medbound Times had an interesting conversation regarding the same with Mohammed Amjad Khan, a Senior Physical Therapist based in Saudi Arabia, who highlighted the following key points to best optimize your workout schedule:
Progressive Overload: Gradually increasing the intensity, duration, or frequency of workouts over time challenges the body to continue adapting and improving.
Periodization: This involves structuring workouts in cycles with varying intensity and focus. For example, a high-intensity phase is followed by a recovery phase with lower-intensity activities. This allows for targeted improvements and prevents overtraining.
Incorporate Variety: Mix up your exercise routine to include a range of activities such as strength training, cardio, yoga, HIIT, etc. This keeps workouts engaging and challenges the body in new ways.
Prioritize Sleep: Never underestimate the importance of a good night’s sleep as it allows your body to recover and maintain healthy metabolism.
Consider individual differences: To extract the maximum benefits from your workouts customize them to your individual body type, goals and needs.
Mindful Eating: Ensuring you stick to a balanced diet and track calorie intake consistently aids your overall progress and puts you in control of your body. No one knows what you need better than you yourself.
In essence, while workouts may not work like miracles on their own, when combined with a balanced calorie intake, they are a vital piece of the puzzle in your journey toward overall health and well-being. The gift of being able to move your body and utilize it to its full potential is the real hype one should be motivated by.
Your body has a way of adapting to what it endures. Use that to live longer, healthier, and happier.
Marlowe, F. W., Berbesque, J. C., Wood, B. M., Crittenden, A. N., et al. (2012). The Hadza: Hunter-gatherers of Tanzania, PLOS ONE, 7(7), e40503.
Pontzer, H., Raichlen, D. A., & Wood, B. M. (2015). Hunter-gatherer energetics and human obesity. Current Biology, 25(20), 2652-2656.
Westerterp, K. R. (2013). Long-term effect of physical activity on energy balance and body composition. British Journal of Nutrition, 107(10), 1465-1477.
Ellison, P. T. (2003). Energetics and reproductive effort. American Journal of Human Biology
Katzmarzyk, P. T., & Lear, S. A. (2019). Physical inactivity and obesity: Links with body composition, morbidity, and mortality. Nature Medicine, 25(9), 1359-1370.
