New research from the University of Basel has found that strength training releases a chemical called BDNF (brain-derived neurotrophic factor), which reduces endurance muscle in the long term. This discovery could lead to new therapies for age-related muscle loss. The study, published in the journal PNAS, analysed the effects of BDNF on endurance muscle. The chemical is a myokine, a hormone-like substance released by muscles during contraction. The research team found that BDNF transforms neuromuscular synapses, which control muscle contraction, and is produced by muscles themselves. The transformation of synapses caused by BDNF leads to an increase in strength muscle and a decrease in endurance muscle. The study suggests that these findings could be used to combat age-related muscle loss.
The human body is made up of two types of muscle fibres: slow-twitch fibres, which provide endurance, and fast-twitch fibres, which provide strength. Professional athletes have long recognised the importance of training both types of fibres. However, until recently, the correlation between the two types of fibres was unknown. The research team at the University of Basel found that BDNF, which plays a crucial role in the formation of strength muscle fibres, reduces endurance muscle during strength training. The study used lab mice to show that BDNF transforms neuromuscular synapses, which control muscle contraction. The chemical is produced by muscles themselves and is different from other myokines.
The study’s lead author, Christoph Handschin, said that the discovery was “interesting” because BDNF is produced by muscles themselves and not just acting on them. The transformation of synapses caused by BDNF leads to an increase in strength muscle and a decrease in endurance muscle. The study suggests that these findings could be used to combat age-related muscle loss. A further investigation showed that muscles without BDNF had fewer age-related limitations than muscles with the chemical. This unexpected result could be used for therapeutic approaches to age-related muscle loss.
