The enhancement of m-ATPase activity during resistance training and consequent performance gain

Muscle contraction is a complex physiological phenomenon involving several proteins. Two of the most important proteins are myosin, which forms the thick filament, and actin, which forms the thin filament. Myosin has a long, fibrous tail and a globular head, which binds to actin when actin is exposed to calcium ions. The energy source for muscle movement is ATP which is transformed to ADP when binding to the actin-myosin complex under the action of an enzyme myofibrillar ATPase (m-ATPase).

Skeletal muscles show remarkable plasticity that permit functional adaptations in response to different stimulations. To date, modifications of the proportions of myosin heavy isoform chains and increases in fiber size, are considered to be the main factors providing sarcomeric plasticity in response to resistance training. In a recent study originating from the Universities of Montpellier and Perpignan, Robin Candau et al. (DOI: 10.113/EP087071) examine the effects of resistance training on gains in the external mechanical power output developed during climbing and myofibrillar ATPase activity in rats.

A 4-week training session did indeed lead to a significant increase in muscle mass and total mechanical power output. Using a micro-volume quench flow QFM-4000, the author showed in this experiment that resistance training also increases the myofibrillar ATPase activity in the different muscles involved during the climbing effort.

Quench flow is a rapid kinetics technique where a chemical reaction is initiated by mixing two reactive solutions. The reaction is then stopped at a pre-defined time by the user, by mixing in a third solution called ‘the quencher’. Once the reaction has stopped, the aged solution is analyzed using sophisticated analytical instrumentation.

Data fitting reveals that these functional improvements are explained by an increase in the rate constant for the release of ATPase hydrolysis products which contribute to performance gains. For the article please click here