The scientists compared short, explosive contractions lasting less than one second with sustained contractions lasting three seconds. They investigated the effect of the different contractions on the participants’ quadriceps muscles located on the front of the thigh.
What’s the difference between muscles, tendons and ligaments?
One group did the explosive contractions, one group did the sustained contractions, and a third group acted as a control group. The participants trained with 40 contractions repeated three times a week for three months. The force produced by every contraction was prescribed and monitored to ensure it was either explosive or sustained. An extensive range of performance and physiological measurements were done before and after the training to assess the changes.
The results showed that explosive contractions are an easier and less tiring way of increasing strength and functional capacity of the muscles, and therefore a highly efficient method of training. The method increases strength by assisting the nervous system in ‘switching on’ and activating the trained muscles. In comparison, the more traditional sustained contractions — which demand a lot of effort and soon become tiring — are actually a more effective way of increasing muscle mass. Increasing muscle mass may be the main training goal for some people, including athletes in some sports, for aesthetic reasons or metabolic health.