Breaking up your sitting time with evening exercise can help you sleep about 30 minutes longer

In a recently published study, BMJ Open Sports & Exercise Medicine, Researchers evaluated whether taking a three-minute resistance exercise break in the evening improves the quantity and quality of sleep compared with prolonged sitting.

study: Regular nighttime activity breaks extend subsequent free-living sleep duration in healthy adults: a randomized crossover trialImage credit: faithie/Shutterstock.com

background

Lack of sleep negatively impacts your diet and increases the risk of cardiometabolic diseases such as coronary heart disease (impaired blood supply to the heart) and type 2 diabetes (high blood sugar due to insulin problems).

Although exercising in the evening generally does not disrupt sleep and improves sleep quality, current guidelines do not recommend exercising before bedtime.

The impact of regular nighttime activity breaks on sleep is unclear. Further research is needed to investigate the long-term effects of nighttime activity breaks on sleep quality and overall cardiometabolic health.

About the Research

This randomized crossover trial, conducted in Dunedin, New Zealand, investigated the effects of a nighttime activity break on sleep and physical activity patterns in 30 participants aged 18-40 years.

Participants were non-smokers, did not take any medications that affect metabolism, and reported being sedentary. Participants wore an ActiGraph GT3X+ accelerometer for seven days to track their habitual activity and sleep, and kept a diary of non-wearing and sleep details.

Participants completed two 4-h overnight sessions on Tuesday or Thursday, with a minimum 6-day washout period, of either extended sitting or sitting with 3-minute resistance exercise breaks every 30 minutes.

On each day, a standardized meal was provided by 14:00 and participants avoided strenuous physical activity according to the pre-intervention protocol.Data were analyzed using mixed-effects regression models to compare sleep and activity outcomes between conditions.

research result

The study was conducted between March and October 2021 and reached the planned sample size of 30 participants, primarily New Zealand European women.

Based on pre-intervention habitual accelerometer data, participants averaged 7 hours 47 minutes of sleep, 10 hours 31 minutes of sitting time, and 4 hours 55 minutes of physical activity per day. 75% of participants had optimal sleep duration and 21% were short sleepers (<7 時間)、4% は長時間睡眠者 (>It took 9 hours.

During the first nighttime period, the regular activity break intervention significantly increased sleep time by 29.3 minutes (95% CI: 1.3 to 57.2, p = 0.040) compared with prolonged sitting.

Total sleep time after the activity break (7 hours 12 minutes) was also significantly longer by 27.7 minutes (95% CI: 2.3 to 52.4, p = 0.033) compared with prolonged sitting (6 hours 45 minutes).

However, there were no significant differences in sleep efficiency, wake-on-sleep (WASO), or number of awakenings between the two conditions. There was no significant difference in the time participants attempted to fall asleep, but wake-up times after the activity break (8:06 AM) were later than those after prolonged sitting (7:35 AM).

No significant differences were found in physical activity patterns within the 24 hours following each intervention.

Regular activity breaks reduced total physical activity by 18 min and active waking time by 1.6% compared with prolonged sitting, but these differences were not statistically significant (95% CI: −50.3 to 13.8, p = 0.265; 95% CI: −4.6 to 1.4, p = 0.289).

Health-promoting effects of regular activity breaks included increases in total sleep time (effect size 0.38 SD, 95% CI: 0.01 to 0.75) and sleep duration (effect size 0.42 SD, 95% CI: 0.01 to 0.82), with a small, non-significant decrease in sedentary time.

Changes in sleep efficiency, total physical activity, WASO, and number of awakenings were all small and non-significant (effect size <0.3).

No significant differences were found in sleep or activity measures across the entire 48-hour period following each intervention: the mean difference in sleep duration comparing normal activity breaks with extended sitting was 0 minutes (-20.5 to 20.5, p>0.999).

Conclusion

This study is the first to investigate the effects of an evening resistance exercise break on sleep quality and physical activity patterns in healthy adults.

Results showed that regular nighttime activity breaks significantly improved free time and total sleep time without compromising sleep quality or other physical activity.

This adds to the growing evidence that nighttime exercise doesn't impair sleep quality. Unlike high-intensity aerobic exercise, resistance exercise breaks can be easily incorporated into your nighttime routine without major interruptions.

The study highlights that an evening exercise break could extend sleep duration and improve long-term health outcomes.