Weight lifting and other types of resistance training produce “reliable and robust decreases in anxiety,” but only when the exercises are performed at moderate-to-low intensities, according to a review of the current scientific research published July 10 in Frontiers in Psychology.
“Numerous studies have documented the beneficial effects of resistance exercise on strength and performance-related outcomes, including increases in muscle mass, bone density, and endurance,” Justin C. Strickland and Mark A. Smith wrote in their article. “This research also indicates that the benefits of resistance exercise extend beyond muscle and tissue growth and include alterations in neurobiological systems relevant to mental health and anxiety-related outcomes.”
At least 13 studies have examined whether a single-bout of strength training can reduce anxiety. But studies on high-intensity resistance training have failed to find any evidence that the exercise session reduced anxiety, and sometimes the high-intensity training increased anxiety.
Studies that included moderate- to low-intensity resistance training, however, consistently found a decrease in anxiety. In other words, participants who performed 20 repetitions of a lower weight were more likely to have reduced anxiety afterward, while those who performed 8 repetitions of a greater weight were not.
“The duration of rest intervals between sets may also play an important role in the anxiolytic effects of resistance exercise, given that exercise performed at low intensities with long rests between sets (i.e., 50–55% 1RM and 90s) produced robust decreases in state anxiety relative to high intensities with short rests,” the authors noted.
Twelve studies on long-term resistance training have found similar results.
“Concordant with single-bout outcomes, the effects of resistance training on anxiety are moderated by exercise intensity, with the most robust decreases observed at low-to-moderate intensities.”
Strickland and Smith said that nearly all the research on resistance training and anxiety had been conducted on healthy participants, and most studies examined college students. Only a single study examined whether resistance training could help treat anxiety disorders.
“Under both single-bout and long-term training conditions, resistance exercise produces anxiolytic effects in a variety of populations. Future research will be necessary to translate these effects to a broader clinical environment; however, enough data exist to begin making recommendations for the design and implementation of resistance exercise-based treatments for anxiety disorders,” they concluded.
