Trunk muscle endurance, hip muscle strength (dynamometer) and gait speed were evaluated.

"Anytime you're in an anabolic state or building muscle," Pipitone says, "such as if you're an extreme endurance athlete, training for a marathon, or you're a body builder."

After all, as Dr Schindall points out, animals use two types of muscle fibre: one for endurance and one for rapid movements.