This study revealed a significant inverted U-shaped relationship between weekday sleep duration and eGDR, identifying an optimal duration of approximately 7.32 hours, and that weekend catch-up sleep is beneficial only in moderation and specifically for those with weekday sleep debt, whereas it may be detrimental for those who already sleep sufficiently.
Key Findings
Results
An inverted U-shaped relationship exists between weekday sleep duration and estimated glucose disposal rate (eGDR), with an inflection point at 7.32 hours.
Restricted cubic splines (RCS) modeling was used to assess the nonlinear association between sleep duration and eGDR
Below the 7.32-hour threshold, increased sleep was positively associated with eGDR (β=0.273, 95% CI 0.224 to 0.322, p<0.001)
Above the 7.32-hour threshold, increased sleep was inversely associated with eGDR (β=-0.222, 95% CI -0.272 to -0.171, p<0.001)
The analysis included 23,475 participants from NHANES 2009-2023
Piecewise regression analyses were conducted based on the identified inflection point to evaluate threshold effects
Results
For individuals with less than 7.32 hours of weekday sleep, 1-2 hours of weekend catch-up sleep (WCS) was associated with higher eGDR compared with no WCS.
1-2 hours of WCS was associated with increased eGDR (β=0.296, 95% CI 0.107 to 0.484, p=0.002) compared with no WCS
This positive association was specific to those with weekday sleep duration below the 7.32-hour threshold
Multivariable regression models were used to analyze the associations between different weekday sleep duration categories, WCS, and eGDR
eGDR serves as a reliable marker of insulin resistance (IR)
Results
More than 2 hours of weekend catch-up sleep negatively moderated the relationship between weekday sleep and eGDR.
The >2 hours WCS group showed a negative moderation effect (β=-0.568, 95% CI -0.970 to -0.167, p=0.005)
This negative association applied to those who already had sufficient weekday sleep
The finding suggests that excessive weekend catch-up sleep may be detrimental for those who already sleep sufficiently
Generalized linear models and multivariable regression models were used to evaluate these associations
Methods
The study used a cross-sectional design drawing from the National Health and Nutrition Examination Survey (NHANES) spanning 2009-2023.
Total sample size was 23,475 participants
The study examined weekday sleep duration, weekend catch-up sleep, and eGDR as primary variables
Restricted cubic splines (RCS), generalized linear models, and multivariable regression models were employed as analytical methods
The cross-sectional design limits causal inference
Conclusions
The findings underscore the importance of personalized sleep recommendations for metabolic health.
Optimal weekday sleep duration for insulin sensitivity as measured by eGDR was identified as approximately 7.32 hours
Weekend catch-up sleep benefits were conditional on having a weekday sleep deficit
Excessive catch-up sleep (>2 hours) was associated with worse insulin resistance markers
The authors highlight that 'WCS is beneficial only in moderation and specifically for those with weekday sleep debt'
What This Means
This research suggests that the relationship between how long you sleep on weekdays and your body's ability to process blood sugar follows an inverted U-shape — meaning both too little and too much sleep are associated with poorer insulin sensitivity. Using data from nearly 23,500 Americans collected between 2009 and 2023, researchers found that sleep duration of approximately 7.32 hours per night on weekdays was associated with the best scores on a measure called the estimated glucose disposal rate (eGDR), which reflects how well the body responds to insulin. Sleeping less or more than this amount was linked to lower eGDR scores, suggesting a higher degree of insulin resistance.
The study also examined whether sleeping extra hours on weekends — often called 'catch-up sleep' — could offset the effects of insufficient weekday sleep. For people who were not getting enough sleep during the week (less than 7.32 hours), catching up with 1-2 extra hours on weekends was associated with better insulin sensitivity. However, sleeping more than 2 extra hours on weekends was linked to worse outcomes, particularly for people who already slept enough on weekdays. This suggests that weekend catch-up sleep is only helpful within a moderate range and only for those who are genuinely sleep-deprived during the week.
This research suggests that sleep habits are an important factor in metabolic health, and that both the amount of weekday sleep and the pattern of weekend catch-up sleep matter. The findings highlight that 'one size fits all' sleep advice may not be appropriate — those who are chronically short on sleep during the week may benefit from modest catch-up sleep on weekends, while those already meeting sleep targets may not benefit and could potentially be harmed by sleeping much longer on weekends. Because this was a cross-sectional study (a snapshot in time), it cannot prove that sleep patterns directly cause changes in insulin resistance, and further research is needed to confirm these relationships.
Fan Z, Wei R, Chen T, Yan X, Yin S, Cao Y, et al.. (2026). Association of weekday sleep duration and estimated glucose disposal rate: the role of weekend catch-up sleep.. BMJ open diabetes research & care. https://doi.org/10.1136/bmjdrc-2025-005692