Long-term exercise for telomeres

We can influence the length of our telomeres,* as discussed in this recent NYT Well blog.

This study highlights the importance of long-term exercise. They compared telomere length in both young athletes (average age ~20, running ~45 miles/week) and aged athletes (average age ~51, running ~50miles/week) compared with non-athletic controls.

• Young athletes and young controls had no difference in their telomere lengths. Not surprising since all young people will have relatively long telomeres - they haven't lived long enough for their cells to "age."
• Sedentary older subjects had a significant decrease in telomere length. Their telomeres were 40% shorter compared with their sedentary young counterparts.
• Aged athletes maintained their telomere length -- aged runners had telomeres only 10% shorter compared to the young runners. Long-term running reduced telomere loss by 75%! 

The conclusion: Long-term continuous exercise maintains telomere length. And as one of the authors of the study, Dr. Christian Werner, said, exercise "at the molecular level has an anti-aging effect."

As discussed in this earlier post, the same group published a related study with findings from both mice and human studies on how physical exercise works at the molecular level:

1) Mice were randomized to voluntary running on a wheel or no running for 3 weeks. Running mice had increased telomerase activity (and other proteins influencing telomeres and cell longevity) in the aorta and circulating blood cells. 

2) Young and middle-aged track and field human athletes were compared with non-athletic controls, looking at telomere length in circulating blood cells. Athletes had increased telomerase, increased telomere-stabilizing proteins, and decreased shortening of their telomeres. 

We now know that long-term exercise keeps our cells molecularly young, and also keeps us looking younger – this study found that people who simply look younger have longer telomeres. And as Dr. Werner said:

"[It] was striking, to see in our study that many of the middle-aged athletes looked much younger than sedentary control subjects of the same age."  

There are still so many questions… how much do we have to exercise to influence our telomeres? What is the effect of other factors like diet, stress, sleep, illness, medications? Is this the same in women, and what role does estrogen play?

*Brief recap on telomeres & telomerase

Telomeres are the pieces of DNA that cap the ends of chromosomes and provide stability. Long telomeres are associated with longevity, while short telomeres are associated with many diseases associated with aging including heart disease, cancer risk, Alzheimer’s, and osteoporosis. Telomerase is the enzyme that helps maintain telomere length. Cancer cells with dysfunctional telomere/telomerase activity leads to unregulated growth and immortality (and we do not want cancer cells to be immortal).