Can stretching before training reduce gains in muscle size and strength?
Until recently, pre-exercise stretches was a mandatory ritual. That changed when many studies showed that static stretches before competition or practice decreased strength and power. A study at State University of Campinas (UNICAMP) in Brazil, found this true about pre-workout stretches.
They found practicing static stretches for 10 weeks resulted in lower increases in strength, muscle endurance and muscle size. While compared to not stretching before training.
The weight training program consisted of four sets of leg extensions to failure at 80 percent of one-repetition maximum (1RM). Flexibility is an important fitness component. For best results with muscle gains and strength, stretch after the workout. After working out is the best time because the muscles are warm. Furthermore, warm muscles won’t interfere with movement control.