This week’s discussion article is a second research paper based on the adaptations to exercise observed through signaling pathways. The hypothesis behind this research was that free radicals that are generated during exercise promote the observed exercise-induced adaptations. Although there was initial evidence to support this hypothesis, the research indicated that the hypothesis was only partially correct. The antioxidant MPG was administered during a lengthy endurance exercise program. However, the result was neither improvement in performance or exercise-induced cardiac hypertrophy. Exercise-induced hypertrophy in the untreated group was accompanied by improved intrinsic performance though. This improvement was linked to a larger and more hyper-dynamic heart. It can be concluded that attenuation of exercise-induced redox signaling will also attenuate intrinsic adaptations that lead to a more hyper-dynamic heart.
The significance of the study lies in the redox levels that lead to exercise adaptation. Without adaptation, the athlete is not improving their physiology for exercise. As mentioned within the text of the last discussion article, cardiac hypertrophy can come in at least two forms. One form improved performance while the other form builds the heart with collagen and other material not conducive to performance and attenuates it. This research article points to a third, middle ground adaptation where cardiac hypertrophy does not occur but performance remains the same, or cardiac hypertrophy occurs but without subsequent performance adaptation. Since the supplementation of anti-oxidants has become a fad due to the ability for anti-oxidants to reduce the harmful effects of free radicals, this research has broad implications. Especially when many of these health conscious individuals use exercise as a form of medicine to ward off harmful aging and lifestyle. Without the ability to adapt, as observed by the supplementation of certain anti-oxidants, then the athlete would not benefit in the same sense as they could have. However, it is not determined whether a lack of performance improvement will also not foster improvements in health. Increased circulation, reduced cortisol levels, increased oxygen intake, amongst other benefits of exercise likely occur even during the supplementation of MPG. Therefore, it can be cautioned to the athlete seeking endurance exercise adaptation. It is still undetermined whether the supplementation of MPG has other harmful effects related to adaptations.
This week covers the molecular adaptations to exercise endurance and skeletal muscle fiber plasticity. In this case, the discussion articles over the last two weeks have been extremely relevant. Cardiovascular endurance adaptation, perhaps as complicated, if not more, than resistance training adaptation, is fascinating. The strengths of the research article is that there was enough background support to make claims going forward. The researchers were able to pin point where the research discoveries were relevant, and where further research should cover. The weaknesses of the research article is that it’s not clear what the consequences of supplementing anti-oxidants really is, besides spinning our wheels trying to improve. Although important, and beneficial, the paper could be aided by a call to action for why this research should be well known. Another strength of the article is that this underlying pathway that is being discussed, and the mode from which it is blocked, is very likely related to many “plateaus” that are seen amongst exercisers. Finding the related exercise pathway, and the reasoning behind the stall in improvement, is a new frontier of exercise physiology.
Learning to apply the research will be difficult. The knowledge that adaptation can be blocked due to the stated reasons is valuable in itself. Perhaps it will be outside the scope of the students within this class to diagnose or evaluate why a given person has seen diminishing returns in their workout program. For some of us, I believe we will forge forward to understand this and make it part of the scientific process of exercise adaptation that we implement in our training programs for ourselves and others. In this case, the research is valuable in of itself. It has inspired myself, and likely others, to re-examine the way we understand exercise.