Telomeres and Exercise: How Much Is Enough?
Telomeres are the protective endings of chromosomes, offering defense against cellular damage that may harm the human body. Telomeres require the assistant of telomerase, an enzyme that elongates chromosomes and ultimately replenishing telomeric DNA to prevent the shortening of telomeres. The fate of both are largely dependent on modifiable and unmodifiable factors. So if you were told you could add on years to a healthy life by dismissing a sedentary lifestyle, would you?
What if you could also lose weight, fight against osteoporosis, lower cholesterol levels and heart disease risk, improve mood, and several other advantages without any sort of side effects? Taking the time to get active may just be your ticket to health!
Exercise and Telomeres
Exercise has shown to play a large part in telomere health primarily related to its ability to lower oxidative stress and inflammation. In fact, people who exercise are shown to spend less time in an oxidative state; the toxic condition is associated to early aging and the onset of the disease-span, including heart disease, cancer, arthritis, and age-related conditions.
While it is already not so surprising exercise displays significant advantages to telomere health, a unique study not only validates the notion, but aims to determine if specific exercises benefit one over the other. To determine if there are preferential exercises when it comes telomere lengths, researchers compared three exercise regimens: moderate aerobic exercise, high-intensity interval training (HIIT), and resistance training. Findings demonstrated individuals who performed moderate aerobic endurance exercise for 45 minutes three times per week, over a six-month span, increased telomerase activity two-fold.
Unlike moderate aerobic and HIIT exercises, resistance training did not lead to significant effects on telomerase. However, all three exercises led to improvements in proteins that help maintain telomere health. And regardless of the type of exercise completed, individuals who increased fitness levels increased activity in their telomerase.
Studies have also demonstrated telomeric health is individually-based on personal levels and completing exercise should be at a moderate pace. For instance, individuals at a lower fitness level are encouraged to slowly build exercise capacity, while naturally "fit" people still need to implement a regular program. Exercise also releases endorphins, also known as the "feel good" hormone, and acts powerful stress-reliever. And considering high-stress can negatively consequence telomeric health, there is just one more validated reason to get active!
How Much Is Enough?
Although it is known the physical act of completing exercise is necessary, this may spark the curiosity on just how much is enough. A study published in the American Journal of Epidemiology helps strengthen the telomere-exercise relationship by studying telomere length in sedentary women. The findings suggest women who exercised less than 30 minutes a day, along with staying sedentary for over 10 hours, had biologically older cells compared to their chronological age. Conversely, women who completed 30 minutes of moderate-to-vigorous activity maintained telomere length, even despite long sitting periods.
Considering the value of exercise on telomere length, it would appear the more exercise the better. And while ultra-endurance athletes have shown to add on years of life compared to sedentary individuals, their telomere length is marginal compared to those who partake in regular, moderate activity. Over-trainers may even display opposing telomeric results, particularly in individuals who have developed fatigue-overtraining syndrome, a condition caused by overuse and damage to the muscle cells following rigorous exercise. Interestingly, the syndrome can occur in beginner and advanced athletes, as it develops not based on experience level, but on the premise of too much training and not enough rest and recovery. If you are an extreme athlete, working with a training expert or physician is encouraged to lessen the risk of fatigue-overtraining syndrome.
The Bottom (Finish) Line
Cardiovascular fitness has shown to significantly support telomere health, with the American Heart Association further recommending individuals should partake in moderate-to-vigorous aerobic activity at 150 minutes a week for heart health. However, strength training should not be discounted. Ongoing and consistent resistance training nurtures balance, preserves and grows muscle mass, and conserves bone density and strength, all vital factors for healthy aging.
Ultimately, any movement is better than no movement, as research shows individuals living a sedentary lifestyle have shorter telomeres compared to people who are even slightly active. So whether riding your bike to work or lifting weights, researchers advocate it is not the single act of working out that supports telomeric health, but overall fitness levels that occur overtime from living an active lifestyle!