Does Muscle Mass Affect Running Times in Male Long-distance Master Runners?
OBJECTIVE
The aim of the present study was to investigate associations between skeletal muscle mass, body fat and training characteristics with running times in master athletes (age > 35 years) in half-marathon, marathon and ultra-marathon.


METHODS
We compared skeletal muscle mass, body fat and training characteristics in master half-marathoners (n=103), master marathoners (n=91) and master ultra-marathoners (n=155) and investigated associations between body composition and training characteristics with race times using bi- and multi-variate analyses.


RESULTS
After multi-variate analysis, body fat was related to half-marathon (β=0.9, P=0.0003), marathon (β=2.2, P<0.0001), and ultra-marathon (β=10.5, P<0.0001) race times. In master half-marathoners (β=-4.3, P<0.0001) and master marathoners (β=-11.9, P<0.0001), speed during training was related to race times. In master ultra-marathoners, however, weekly running kilometers (β=-1.6, P<0.0001) were related to running times.


CONCLUSIONS
To summarize, body fat and training characteristics, not skeletal muscle mass, were associated with running times in master half-marathoners, master marathoners, and master ultra-marathoners. Master half-marathoners and master marathoners rather rely on a high running speed during training whereas master ultra-marathoners rely on a high running volume during training. The common opinion that skeletal muscle mass affects running performance in master runners needs to be questioned.
Institute of General Practice and for Health Services Research, University of Zurich, Zurich, Switzerland ; Gesundheitszentrum St. Gallen, St. Gallen, Switzerland.
Beat
B
Knechtle
Christoph Alexander
CA
Rüst
Patrizia
P
Knechtle
Thomas
T
Rosemann
Anthropometry; Body Fat; Running; Skinfold Thickness; Sports