Telomeres and exercise
Whatever the recommendations or the ailment may be, they all seem to end up with: get enough sleep, proper nutrition, and practice exercise – it has become the mantra. Benefits associated with exercise have been proven repeatedly, from improving our cardiovascular health, regulating digestive processes, and putting us in a better mood!
What about aging? It sounds logical that exercise would contribute to decreasing the pace of aging, but what happens at a molecular level is still being studied.
As humans with a limited lifespan, aging is a constant source of concern. Going far beyond the aesthetic implications, aging is linked to tissue degeneration; our tissues lose their ability to regenerate. This diminished capacity is ruled by genetic factors and environmental ones, and lifestyle choices that hurt the delicate balance between repair and damage. When tissues cannot longer replace damaged cells, many illnesses arise, especially those such as type II diabetes and Alzheimer’s. Novel studies claim that: “A well-established marker of the aging process is the length of the protective cap at the ends of chromosomes, called telomeres.”
Telomeres and Aging
Is there a link between telomere activity and exercise stimuli? Only recently, telomeres have acquired a widely accepted relevant place in studying aging processes. These repetitive sequences at the end of our chromosomes shorten with each cell division – a phenomenon called the end-replication problem.
Molecular improvement, such as telomere activity improvement, thanks to regular exercise, has only been elucidated. Several studies have found a promising correlation between physical activity and telomere length. In contrast, individuals who practice some form of physical activity have longer telomeres in immune cells than their sedentary peers. Moreover, other studies imply a telomere-protective phenotype triggered by exercise. This crucial cellular adaptation is believed to slow the onset of age-related diseases. Interestingly, different lines of evidence show that telomeres shorten even more when the body endures long-term high-intensity training.
Along with these findings, other studies have researched the stress-buffering action that exercise could potentially provide to individuals. However, these same researchers have discovered that not all people under stress have significantly shorter telomeres. The theory indicates that in sedentary people, chronic stress could trigger short telomeres; however, in active individuals, stress would not change telomere length at all.
Consistent with other studies, these sedentary individuals enduring high levels of stress can protect their telomere activity and reduce the pace of aging when they begin to practice physical activity regularly.
The charts below show the different findings from distinct studies in which exercise had a positive outcome in telomere length:
Telomeres, aging, and exercise -what kind of exercise works?
A study published by the European Heart Journal followed 124 individuals over six months. The subjects were asked to practice exercise in three different modalities: resistance training (weight-lifting, resistance bands, or bodyweight training), endurance training (running, swimming, cycling), or HIIT (high-intensity interval training).
After six months, the study concluded that those individuals who practiced HIIT and endurance training increased telomere activity, benefiting cell regeneration; this was not the case with resistance training, in which individuals remained the same in that particular aspect. The conclusion was simple: HIIT and endurance training trigger an anti-aging effect.
An important fact to highlight is that after those weeks, all participants improved their fitness levels, increased lean mass, and boosted their insulin sensitivity, even those whose telomerase activity was unaffected.
Telomeres and exercise – HIIT training
HIIT combines short bursts of high-intensity exercises followed by short breaks. People training HIIT regularly achieve between 80% and 95% of their top heart rate. Activities include push-ups, squats, jumping jacks, burpees, jumping squats, and high kicks, to name a few. Health specialists do not recommend abusing HIIT training because of the arduous effort on the body.
Telomeres and exercise – Endurance training
Endurance training involves continued, more extended periods of exercises performed just below max heart intensity ranging from 30 minutes to a few hours. The most popular and effective forms of endurance training are running, swimming, and cycling.
The molecular mechanisms in which exercise impacts telomerase are still somewhat unknown. So far, studies conclude the relevance of promoting physical activity -especially in stressed individuals -to regulate telomerase activity and produce an anti-aging effect. The contradiction is that highly-stressed individuals are less likely to practice physical activities. Contextual factors such as motivation, personality, and environment should be studied further to promote physical exercise.