It is well known to most that physical activity and exercise can exert positive effects upon our health and wellbeing. The fields of epidemiology and exercise physiology have yielded insights into the amount of physical activity we should be performing, with more typically being better; and that the harder the physical activity is, the greater the benefit received independently of the amount. Many have argued that the benefits received from physical activity and exercise come from our evolutionary history where we were typically far more active than we are today. That our bodies evolved to be active. Some have even gone so far as to offering recommendations for how to achieve ‘evolutionary’ or ‘paleo’ fitness (Cordain et al., 1998; O’Keefe & Cordain, 2004; O’Keefe et al., 2010; 2011).
These recommendations consider ‘what should we do?’ based upon the evolved traits in humans that determine our physical activity capacities and limitations (i.e. ‘what can we do?’), and with respect to emulating the physical activity patterns of extinct or extant hunter gatherers (i.e. ‘what did we do?’).
But, are narratives regarding evolutionary rationales and recommendations for physical activity and exercise a convenient ‘just so’ story?
Paleo-archaeology has given us considerable insight into the types of activity Homo sapiens are adapted for and what we are capable of. We have numerous features that indicate we evolved to be able endurance athletes, particularly with respect to bipedal locomotion, and which conferred several adaptive advantages (Bramble & Lieberman, 2004). Further, although we have lost much of the upper body locomotor specialization from our ancestors (Lovejoy, 2009) studies indicate our ancestors likely had well developed upper body musculature and thus physical capacity (Trinkaus et al., 2002). Lastly, as is evident from the field of exercise physiology, our bodies have adapted to be highly plastic with the ability to adapt towards the demands placed upon it (Lieberman, 2012).
Clearly, with respect to the question of ‘what can we do?’, Homo sapiens evolved to be physically capable and able to perform quite a repertoire of physical activity patterns. But, this doesn’t necessarily answer the question of ‘what did we do?’ when it comes to the physical activity patterns of our evolutionary past.
We can learn a lot from our close relatives, other extant primate species, who interestingly (though with obvious variation across species) are probably not as physically active as many would expect. They spend the vast majority of their time resting, typically sitting, and relatively little being what we would consider to be ‘physically active’ (Rose, 1973). It could be argued that primates are actually quite sedentary.
However, the reconstruction of physical activity patterns of extinct Homo sapiens is what some have termed ‘Bio-archaeology’s Holy Grail’ (Jurmain et al., 2012). Understanding the volume, frequency, intensity of effort, and types/modalities of activities performed by extinct humans is not a simple endeavor. Studies of articular modifications, musculoskeletal stress markers, and skeletal robusticity and geometry, though informative, are certainly not something we can reliably use to answer the question of ‘what should we do?’ in order to enhance our longevity and health in the modern world. Indeed, some research would perhaps suggest we should avoid the types of activities our ancestors likely engaged in (Berger & Trinkaus, 1995).
That last point is worth expanding upon. In our evolutionary past our physical activity was directed towards, and evolved enabling, things that would maximize our reproductive success; our evolutionary ‘fitness’ though not in the sense that many of paleo fitness proponents use it. Not all ancestral adaptions are good for us, and many involve trade-offs. Some novel modern behaviors not selected for are not necessarily bad for us either.
With a lack of ability to truly understand the physical activity patterns of our extinct ancestors, studies of extant hunter gatherers perhaps offer the most valuable insight into what physical activity patterns we should be following. Indeed, they typically are more active on the whole than people in modern industrialised populations (Eaton & Eaton, 2003) and spend at least some of their time performing more vigorous intensity of effort activities (Gurven et al., 2013). However, when it comes to the types and modalities of physical activity, these are highly variable and influenced by sexual division of labour, occupation duration, habitat quality, and hunting and logistical mobility (Grove, 2009).
Physical activity recommendations from national and international guidelines have historically been ‘volume-centrique’ with a focus upon how much we should be doing. However, it has recently been argued that perhaps we should be focusing more on how hard the activity we perform is (Steele et al., 2017). We can’t know what our physical activity patterns truly were in our evolutionary past. But, this approach perhaps best matches the physical activity patterns of modern hunter gatherers who have highly variable activity patterns, undulating both within and between days. Indeed, there are poor relationships between physical activity levels and physical fitness in many cases (Lightfoot, 2013) making it unclear from an evolutionary perspective as to whether adaptations drove increased physical activity, or vice versa. In considering the variation in physical activity types and modalities it’s clear that recommendations to engage in any particular one may be folly. Yet, it may not even matter as long as such activities are of a sufficient intensity of effort as recent work suggests the physiological response, and perhaps then the stimulus, to differing modalities differs little (Steele et al., 2018).
It’s highly likely that some degree of mismatch exists between our modern environment and the physical activity levels we have evolved to perform. Yet, despite the lack of clarity as to exactly what the physical activity patterns of our past, what kinds of recommendations could we broadly offer that fit with modern understandings of exercise science:
- Select a modality based upon personal preference (or sporting requirement) whilst considering the potential injury risks associated with it; consider the risk-reward ratio.
- Focus upon utilising a high intensity of effort (preferably maximal or near maximal) at least some of the time whilst performing low intensity of effort activity the majority of the time.
In all likelihood, it’s probably as simple as that.
- Cordain L, et al. Physical activity, energy expenditure, and fitness: An evolutionary perspective. In J Sports Med 1998;19:328-335
- O’Keefe J, & Cordain L. Cardiovascular disease resulting from a diet and lifestyle at odds with our Paleolithic genome: How to become a 21st-Century hunter-gatherer. Mayo Clin Proc 2004;79:101-108
- O’Keefe J, et al. Organic fitness: Physical activity consistent with our hunter-gatherer heritage. Phys Sportsmed 2010;37:11-18
- O’Keefe J, et al. Exercise like a hunter-gatherer: A prescription for organic physical fitness. Prog Cardiovasc Dis 2011;53:471-479
- Bramble DM, & Lieberman DE. Endurance running and the evolution of Homo. Nature 2004;432:345-352
- Lovejoy CO. Reexamining human origins in light of Ardipithecus ramidus. Science 2009;326:e1-8
- Trinkaus E, et al. Upper limb versus lower limb loading patterns among near eartern middle Paleolithic hominds. In: Akazawa T, et al. Neanderthals and modern humans in western Asia. Springer: Boston, MA, 2002
- Lieberman DE. What are humans adapted for? Presented at the Ancestral Health Symposium 2012 – https://www.youtube.com/watch?v=Txrs-FLz64Y&t
- Rose MD. Quadrupedalism in primates. Primates 1973;14:334-357
- Jurmain R et al. Chapter 29. Bioarchaeology’s Holy Grail: The reconstruction of activity. In: Grauer AL. A Companion to Paleopathology, Blackwell 2012
- Berger TD, & Trinkaus E. Patterns of trauma among the Neandertals. J Archaeol Sci 1995;22:841-852
- Eaton SB, & Eaton SB. An evolutionary perspective on human physical activity: implications for health. Comp Biochem Physiol A Mol Integr Physiol 2003;136:153-159
- Gurven M et al. Physical activity and modernization among Bolivian Amerindians. PLoS One 2013;8:e55679
- Grove M. Hunter-gatherer movement patterns: Causes and constraints. J Anthropol Archaeol 2009;28:222-233
- Steele J et al. A higher effort-based paradigm in physical activity and exercise for public health: making the case for a greater emphasis on resistance training. BMC Public Health 201717:300
- Lightfoot JT. Why control activity? Evolutionary selection pressures affecting the development of physical activity genetic and biological regulation. BioMed Res Int 2013;821678:1-10
- Steele J et al. Similar acute physiological responses from effort and duration matched leg press and recumbent cycling tasks. PeerJ 2018;6:e4403