Thanks for writing this! It was useful when organising my workout routine.
I read the Kovacevic et al paper on sleep you cite, and there are some caveats probably relevant to some LW readers. In particular, the benefits are less clear for younger adults.
Acute resistance exercise studies
“There was some evidence that an acute bout of resistance exercise may reduce the number of arousals during sleep”
They base this on three studies. The cohorts are elderly (65-80 years), middle-aged (mean 44.4 +- 8 years), and young (21.9 +- 2.7 years). They note that “in the final study in healthy young-to-middle aged adults, no effects were observed on sleep quality measured using accelerometry, or on 5- and 7-point Likert scales following an acute bout of resistance exercise”
Chronic resistance exercise studies
“Overall, the data suggest that chronic resistance exercise has significant benefit on subjective sleep quality”
They base this on seven studies. “All four studies performed in older adults reported significant improvements in sleep quality...however, results were inconsistent for younger adults, with only one out of three studies reporting significant improvements.” (the study with the significant improvements was of young women).
The above results focus on sleep quality, because as you say, sleep quantity tends not to be much influenced resistance training. Nevertheless, note the following:
“The remaining study in younger adults (many with insomnia) reported a large but non- significant negative effect on sleep duration following moderate-intensity resistance training on both weekdays and weekends.”
I was curious to see if this apparent age effect exists for aerobic exercise. The Kovacevic et al cite the following Kredlow et al paper as a “recent review of aerobic exercise” https://www.ncbi.nlm.nih.gov/pubmed/25596964. Indeed it seems to be predominantly about aerobic exercise, but also covers some anaerobic exercise studies. According to Kovacevic et al has 10 fewer papers on resistance training than their paper, which by my count makes it 11 resistance training papers. Kredlow et al write:
“For the majority of outcomes, there is no difference for the benefits of exercise on sleep depending on age or sex. We did, however, find significant differences for certain sleep variables. Specifically, the benefits of acute exercise did not vary by age...the benefits of regular exercise did not vary by sex and for one variable (sleep onset latency), appeared to be stronger for younger than older individuals.”
Overall, it’s quite unclear to me whether resistance exercise has sleep benefits for younger adults, and the evidence for aerobic exercise seems stronger (although I’d like to find a review solely of aerobic exercise studies).
Thanks for writing this! It was useful when organising my workout routine.
I read the Kovacevic et al paper on sleep you cite, and there are some caveats probably relevant to some LW readers. In particular, the benefits are less clear for younger adults.
Acute resistance exercise studies
“There was some evidence that an acute bout of resistance exercise may reduce the number of arousals during sleep”
They base this on three studies. The cohorts are elderly (65-80 years), middle-aged (mean 44.4 +- 8 years), and young (21.9 +- 2.7 years). They note that “in the final study in healthy young-to-middle aged adults, no effects were observed on sleep quality measured using accelerometry, or on 5- and 7-point Likert scales following an acute bout of resistance exercise”
Chronic resistance exercise studies
“Overall, the data suggest that chronic resistance exercise has significant benefit on subjective sleep quality”
They base this on seven studies. “All four studies performed in older adults reported significant improvements in sleep quality...however, results were inconsistent for younger adults, with only one out of three studies reporting significant improvements.” (the study with the significant improvements was of young women).
The above results focus on sleep quality, because as you say, sleep quantity tends not to be much influenced resistance training. Nevertheless, note the following:
“The remaining study in younger adults (many with insomnia) reported a large but non- significant negative effect on sleep duration following moderate-intensity resistance training on both weekdays and weekends.”
I was curious to see if this apparent age effect exists for aerobic exercise. The Kovacevic et al cite the following Kredlow et al paper as a “recent review of aerobic exercise” https://www.ncbi.nlm.nih.gov/pubmed/25596964. Indeed it seems to be predominantly about aerobic exercise, but also covers some anaerobic exercise studies. According to Kovacevic et al has 10 fewer papers on resistance training than their paper, which by my count makes it 11 resistance training papers. Kredlow et al write:
“For the majority of outcomes, there is no difference for the benefits of exercise on sleep depending on age or sex. We did, however, find significant differences for certain sleep variables. Specifically, the benefits of acute exercise did not vary by age...the benefits of regular exercise did not vary by sex and for one variable (sleep onset latency), appeared to be stronger for younger than older individuals.”
Overall, it’s quite unclear to me whether resistance exercise has sleep benefits for younger adults, and the evidence for aerobic exercise seems stronger (although I’d like to find a review solely of aerobic exercise studies).