Better sleep doesn’t just leave you feeling more rested, it can measurably improve your muscular endurance and aerobic fitness. 

We recruited 30 new Pod members and measured their muscular endurance and aerobic fitness at three time points: before sleeping on the Pod, and after 2 weeks and 1 month of sleeping on the Pod. At each time point, participants completed at least one of three fitness tests, including push-ups, curl-ups, and/or the Cooper’s run test. After the study, a follow-up survey asked participants how they felt the Pod had impacted their sleep and fitness. 

Key takeaways:

1. Aerobic fitness (VO2max) improved by 7% on average after sleeping on the Pod for 2 weeks.
2. Muscular endurance improved the most after sleeping on the Pod for 1 month:
   • Upper body muscular endurance (push-ups) increased by 17%, on average.
   • Abdominal muscular endurance (curl-ups) increased by 19%, on average.

Aerobic performance improved after 2 weeks on the Pod

Aerobic fitness can be measured by a VO2max, which is a measurement of the maximum amount of oxygen (O2) your body can use during aerobic exercise, like running or biking. To estimate VO2max, participants completed the Cooper’s run test, running as far as possible in 12 minutes. 

After sleeping on the Pod for 2 weeks:

• Aerobic fitness (VO₂max via Cooper’s test) improved by 7% on average, with some participants seeing up to a 13% improvement. 

This 7% gain is equivalent to 6-8 weeks of interval training (HIIT class or hill sprints), 3-4 times per week (source).

Muscular endurance improved after 1 month on the Pod

Muscular endurance measures how long muscles can perform repeated movements before fatiguing. In our study, participants performed as many push-ups or curl-ups as possible to a set cadence (standard cadence for everyone), stopping when they could no longer keep pace.

After sleeping on the Pod for 1 month:

• Upper body muscular endurance (push-ups) improved by 17% (+3.5 push-ups) on average, and up to 26% (+6 push-ups) in some participants. 
• Abdominal muscular endurance (curl-ups) improved by 19% (+8.5 curl-ups) on average, and up to 35% (+17 curl-ups) in some participants. 

The Pod improves fitness by improving sleep

Lifestyle surveys completed at each timepoint showed that only 14% of participants changed their exercise routines, so what drove these fitness gains? A follow-up survey assessing perceived sleep quality and energy levels found that 93% of participants reported improved sleep quality and 64% reported increased energy levels. Better sleep on the Pod likely translated into more energy during workouts, so people pushed themselves harder and therefore saw greater gains.

Better sleep is one of the most underrated performance tools available. See how the Pod improves sleep.

Appendix:

Participants & Procedures

Participants (n=30 total unique) completed at least one physical fitness test (push-up: n=28, curl-up: n=21, VO2max: n=17) before sleeping on the Pod and 2 weeks and 1 month after beginning to sleep on the Pod.

The validated fitness tests from the American College of Sports Medicine (ACSM) were:

• Muscular endurance (curl-up & push-up): Measures the maximum number of curl-ups and push-ups, respectively, can be completed consecutively at a specific cadence, without rest, until the cadence is unable to be maintained or the form breaks (i.e. failure).
• Aerobic fitness test (Cooper’s run test; validity): Measures the longest distance that can be run in 12 minutes; this distance can be used to estimate VO2max.

Statistical Analyses

Muscular endurance and aerobic fitness measurements were grouped into “before” and “after” Pod use. Repeated measure ANOVAs with timepoint (before the Pod and 2 weeks and 1 month after the Pod) as a within variable and Wilcoxon signed-rank follow-up tests (with a Bonferroni correction applied) were used to evaluate differences within muscular endurance metrics (push-ups & curl-ups). A paired t-test was used to evaluate differences within aerobic performance between time points. An alpha of 0.05 defined significance for all tests. Participants with reported lifestyle changes that would significantly impact metrics (e.g. increased/decreased training load, surgery, etc.) were excluded from analysis. All findings reported above are statistically significant (P < 0.05) and included participants provided fitness test data (n=30) and responded to the follow-up survey (n=14).