Table 8.
Sleep Behaviors Associated with Energy Drink or Coffee Consumption in the Last Month
| Behavior | <3 Energy drinks in the last month (n = 136), mean (SD) | ≥3 Energy drinks in the last month (n = 23), mean (SD) | T | <16 Coffee drinks in the last month (n = 133), mean (SD) | ≥16 Coffee drinks in the last month (n = 27), mean (SD) | T |
|---|---|---|---|---|---|---|
| Woke up too earlya | 2.06 (1.46) | 2.04 (1.36) | NS | 2.02 (1.38) | 2.26 (1.70) | NS |
| Felt tired during daya | 5.50 (2.00) | 5.65 (2.19) | NS | 5.33 (1.96) | 6.48 (2.06) | −3.59** |
| Nappeda | 2.93 (2.48) | 2.01 (1.20) | NS | 2.90 (1.92) | 2.70 (1.96) | NS |
| Hard time getting to sleepa | 2.19 (1.71) | 3.30 (2.49) | −2.69** | 2.30 (1.87) | 2.59 (1.93) | NS |
| Fell asleep in classa | 1.49 (1.34) | 1.30 (0.77) | NS | 1.39 (1.11) | 1.81 (1.86) | −1.78* |
| Up until at least 3:00 AMa | 2.28 (1.65) | 3.30 (2.49) | −2.53* | 2.39 (1.81) | 2.63 (1.93) | NS |
| Epworth Sleepiness Scale | 7.93 (4.25) | 7.74 (3.74) | NS | 7.71 (4.24) | 8.81 (3.74) | −1.81* |
| Typical bedtime on weekday | 11:56 PM (73 min) | 12:44 AM (86 min) | −2.66* | 12:07 AM (74 min) | 12:01 AM (88 min) | NS |
| Typical rise time on weekday | 7:39 AM (80 min) | 7:51 AM (89 min) | NS | 7:44 AM (85 min) | 7:28 AM (63 min) | NS |
| Total sleep time on weekday | 7.66 h (91 min) | 7.11 h (94 min) | NS | 7.61 h (96 min) | 7.44 h (65 min) | NS |
| Typical bedtime on weekend | 1:41 AM (80 min) | 2:31 AM (103 min) | −2.70** | 1:48 AM (78 min) | 1:47 AM (113 min) | NS |
| Typical rise time on weekend | 10:04 AM (91 min) | 10:39 AM (112 min) | −1.69* | 10:15 AM (90 min) | 9:39 AM (113 min) | 1.72* |
| Total sleep time on weekend | 8.39 h (80 min) | 8.13 (97 min) | NS | 8.44 h (77 min) | 7.88 h (101 min) | 1.99* |
| Number of all-nighters per semester | 3.15 (1.61) | 4.39 (2.13) | −3.26** | 3.27 (1.73) | 3.59 (1.82) | NS |
a
Days per week.
*
p < 0.1, experiment-wise error; **p < 0.007, Bonferroni-type correction.