Skeletal muscle telomere length in healthy, experienced, endurance runners

Abstract

Measuring the DNA telomere length of skeletal muscle in experienced endurance runners may contribute to our understanding of the effects of chronic exposure to endurance exercise on skeletal muscle. This study compared the minimum terminal restriction fragment (TRF) length in the vastus lateralis muscle of 18 experienced endurance runners (mean age: 42 +/- 7 years) to those of 19 sedentary individuals (mean age: 39 +/- 10 years). The runners had covered almost 50,000 km in training and racing over 15 years. Minimum TRF lengths measured in the muscle of both groups were similar (P = 0.805) and within the normal range. Minimum TRF length in the runners, however, was inversely related to their years spent running (r = -0.63, P = 0.007) and hours spent training (r = -0.52, P = 0.035). Therefore, since exposure to endurance running may influence minimum TRF length, and by implication, the proliferative potential of the satellite cells, chronic endurance running may be seen as a stressor to skeletal muscle.

Leukocyte and Skeletal Muscle Telomere Length and Body Composition in Monozygotic Twin Pairs Discordant for Long-term Hormone Replacement Therapy

“…Rae et al reported an inverse relationship between minimum telomere length and long term exposure to endurance exercise (Rae et al, 2010). Kadi et al observed an inverse correlation between minimum SMTL and performance in power lifting .…”

Corpus luteal angiogenesis in a high milk production dairy breed differs from that of cattle with lower milk production levels

“…Moreover, many high-performance athletes that are subject to intense training regimens are known to suffer from premature ageing (Wright 2012) including health problems associated with accelerated senescence (Kurz et al 2004). For example, Rae et al (2010) measured the DNA telomere length of skeletal muscle in experienced endurance runners and found that there is an inverse relationship between exposure to endurance exercise and minimum telomere length, and by implication, the proliferative potential of skeletal muscle satellite cells (stem cells). They concluded that endurance running influenced the proliferative potential of stem cells negatively.…”

The influence of physical exercise and sports on telomere length - A model for telomere length and telomerase activity regulation based on a comparative assessment of literature

“…To determine effects of endurance training in humans, (Rae et al, 2010) obtained detailed training records and minimum TRF length of the vastus lateralis muscle in 17 well recovered 42.4±6.9 year old endurance runners. 455…”

“…satellite cells). TL in satellite cells is of special interest, since exercise acts to particularly damage muscle tissue (Rae et al, 2010), thus requiring enhanced muscle stem cell proliferation. The cell proliferation and therefore the DNA replication is accompanied by telomere shortening due to the end replication problem, on the one hand, and by telomere lengthening via telomerase, on the other.…”

“…Despite physical activity (PA) in general is seen as some sort of a "magic bullet" for the prevention and/or cure of most civilization diseases, at least strenuous physical exercise is known to trigger all three of the known telomere shortening mechanisms: (a) increased damage in skeletal muscle cells and thus increased stem cell proliferation for repair (Karalaki et al, 2009;Natale et al, 2003;Rae et al, 2010), (b) increased ROS levels due to accelerated metabo-35 lism (Radak et al, 2013), and (c) release of inflammatory mediators (Natale et al, 2003). On the other hand, studies also exist that physical exercise may act to enhance (a) telomerase activity (Chilton et al, 2014;Werner et al, 2009), (b) anti-oxidative-enzyme activity (Urso and Clarkson, 2003), and (c) anti-inflammatory functions (Peake et al, 2005).…”