PURPOSE: Aerobic exercise training has many known cardiovascular benefits that may promote healthy ageing. Long-term long-distance running is a common aerobic exercise modality, but the number of individuals involved in endurance running decreases with increasing age. This cross-sectional study assesses structural findings, e.g. body composition, bone mineral density and muscle mass, obtained from middle-aged long-term endurance runners, and compares the findings with matched non-runners. METHODS: Total and regional lean and fat mass (kg) and total body percent lean and fat mass (%) were assessed by DXA and analyzed using enCORE software version 17. Sagittal Magnetic Resonance images using a T2-weighted sequence captured the cross-sectional area and thickness of the multifidus from L1 to L5.
RESULTS: Analyses included 10 male runners with a mean(standard deviation; SD) age of 49(4)yr, height of 178.9(4.9)cm, weight of 67.8(5.8)kg and body mass index (BMI) of 21.4(1.4)kg/m² that had been running 82.6(27.9)km/wk for 23(13)yr and nine non-runner sex-, age-, height- and weight-matched controls with a mean(SD) age of 51(5)yr, height of 176.0(72.8)cm, weight of 72.8(7.1)kg and BMI of 23.7(2.1)kg/m². Only BMI statistically differed between the groups (P=0.010). Runners had 4.4kg greater mean total body lean mass than controls, which equated to 10percentage-points greater mean total body percent lean mass, albeit only the latter was significant (P=0.001). Runners also had 14% greater trunk lean mass. Moreover, runners had less total body (8.6kg), arm (58%), leg (52%), trunk (73%), android (91%) and gynoid fat mass (64%). No differences were observed between groups for BMD outcomes. No between-group differences in multifidus size were observed.
CONCLUSIONS: Middle-aged long-term male runners exhibit lower total body fat percentage and healthier fat storage distribution, but no different BMD compared sex-, age-, height- and weight-matched non-running participants. Other than cardiovascular benefits, long-term endurance running seems to also provide structural benefits.