Independent variables | PARI in sports clubs (no injuries†) | ||||
Crude effect | Model 1 | Model 2 | Model 3 | Model 4 | |
OR (95% CI) | OR (95% CI) | OR (95% CI) | OR (95% CI) | OR (95% CI) | |
Sleep problems | |||||
Sleep problems more than once a week | Ref. | Ref. | Ref. | Ref. | Ref. |
Problems with falling asleep (less than once a week) | 1.37 (1.20 to 1.58)*** | 1.25 (1.07 to 1.46) ** | 1.23 (1.05 to 1.44)* | 1.32 (1.12 to 1.55)*** | 1.32 (1.12 to 1.55) *** |
Waking up at night (less than once a week) | 1.58 (1.36 to 1.83)*** | 1.42 (1.21 to 1.68)*** | 1.40 (1.19 to 1.66)*** | 1.45 (1.23 to 1.72)*** | 1.45 (1.23 to 1.72)*** |
Problem with waking up in the morning and feeling rested (less than once a week) | 1.18 (1.05 to 1.34)** | 0.93 (0.80 to 1.08) | 0.91 (0.79 to 1.06) | 0.95 (0.82 to 1.10) | 0.95 (0.82 to 1.11) |
Day sleepiness (less than once a week) | 1.31 (1.16 to 1.48)*** | 1.20 (1.03 to 1.39)* | 1.17 (1.00 to 1.36)* | 1.28 (1.10 to 1.50)*** | 1.31 (1.12 to 1.53) *** |
Sleep duration‡, school days | |||||
short | Ref. | - - | Ref. | Ref. | Ref. |
normal | 1.44 (1.26 to 1.63)*** | - - | 1.35 (1.17 to 1.55)*** | 1.37 (1.19 to 1.58)*** | 1.37 (1.19 to 1.58)*** |
long | 0.96 (0.31 to 2.94) | - - | 0.79 (0.23 to 2.72) | 0.87 (0.25 to 3.02) | 0.86 (0.24 to 2.99) |
Sleep duration, weekends | |||||
Short | Ref. | - - | Ref. | Ref. | Ref. |
Normal | 1.32 (1.09 to 1.59)** | - - | 1.13 (0.93 to 1.38) | 1.04 (0.85 to 1.27) | 1.03 (0.84 to 1.27) |
Long | 1.22 (0.98 to 1.53) | - - | 1.09 (87 to 1.38) | 1.00 (0.79 to 1.26) | 0.98 (0.77 to 1.24) |
Gender (girls vs boys) | 1.62 (1.43 to 1.83)*** | - - | - - | 1.89 (1.65 to 2.17)*** | 1.91 (1.66 to 2.20)*** |
Age (continuous) | 0.99 (0.95 to 1.03) | - - | - - | - - | 1.03 (0.98 to 1.08) |
Models 1–4: Univariate binary logistic regression analysis was used to assess the crude associations of each of the four sleep problems (model 1) with PARI. Then, we added sleep duration during the schooldays and weekends in the model (model 2) and explored the association with PARI and the modification of the adjusted associations of sleep problems with PARI. Finally, we adjusted regression models for the effect of gender (model 3) and age (model 4).
*p<0.05, **p<0.01, ***p<0.001.
†No injury was used as the dependent variable. The table presents the associations between sufficient sleep duration (normal and long sleep) good sleep quality (no sleep problems) and the likelihood of not having PARI (no injury).
‡Sleep duration was calculated using the cut-offs for short and long sleep duration from Sawyer et al.25
PARI, physical activity-related injury.