Time-restricted feeding in young men performing resistance training: A randomized controlled trial.

Plain-language summary

This study asked whether eating all your daily calories inside a four-hour window, which the authors call time-restricted feeding, changes body composition and strength during resistance training. Young men who lifted weights three days a week were assigned at random either to time-restricted feeding on four days a week or to eating normally, and their body composition, muscle size and strength were measured over eight weeks. On each restricted day the men ate about 650 calories less, which over four days a week is a smaller cut than that spread across the whole week. Total body composition did not change over the eight weeks, and the biceps and the front thigh grew in both groups. The two groups came out ahead of each other on different things: the group lifting without the eating window gained 2.3 kg more lean soft tissue, while the restricted group improved more in upper and lower body strength and lower body endurance. Other time-restricted eating studies in this library used different eating windows, different populations and different measurements, so they are not tests of the same routine.

Key findings

• On each day it was used, the four-hour eating window cut intake by about 650 calories.
• Total body composition did not change over eight weeks, and muscle cross-sectional area grew in both groups.
• The group lifting WITHOUT the eating window gained 2.3 kg more lean soft tissue.
• The group using the eating window improved more in upper and lower body strength and lower body endurance.