PMC

(A) The mean diurnal IOP profiles of 31 PACG patients. (B) The mean diurnal IOP profiles of 22 POAG patients. (C) The diurnal IOP profile of PACG group. The IOP at 08:00 was significantly higher than that at 20:00 (p = 0.001) and 24:00 (p = 0.001). (D) The diurnal IOP profile of POAG group. The IOP at 08:00 was significantly higher than that at 16:00 (p = 0.004), 20:00 (p = 0.004) and 24:00 (p < 0.001) and the IOP at 24:00 was significantly lower than 12:00 (p < 0.001), 16:00 (p = 0.004) and 20:00 (p = 0.002). (E) The frequency of peak diurnal IOP measured in PACG patients. The measurement at 8:00 was higher than that at 20:00 (p = 0.003) and 24:00 (p = 0.001). (F) The frequency of peak diurnal IOP measured in POAG patients. The measurement at 08:00 was higher than that at 16:00 (p = 0.003) and 24:00 (p = 0.001). (G) The frequency of trough diurnal IOP counted in PACG patients. (H) The frequency of trough diurnal IOP counted in POAG patients.

Data are graphed as diurnal differences in order to identify whether exercise attenuated the stress-induced flattening of diurnal physiological rhythms and sleep/wake behavior. (A) Stress exposure reduced nightly wheel running for post-stress days 1–4, but returned to pre-stress levels by post-stress day 5. (B) Stress exposure significantly flattened the diurnal rhythms of locomotor activity in both groups for post-stress days 1–3, but this effect lasted until post-stress day 4 in the sedentary group. Both groups regained their pre-stress diurnal differences in locomotor activity by post-stress day 5 and the diurnal difference in locomotor activity between the exercise and sedentary groups was again evident at this time. (C) Stress exposure flattened the diurnal rhythms of heart rate in both groups for post-stress day 1, but this effect lasted until post-stress day 3 in the sedentary group. (D) Stress exposure flattened the diurnal rhythms in CBT in both groups until post-stress day 2, but this effect lasted until post-stress day 3 in the sedentary groups. Exercise attenuated the impact of stress on flattening of the diurnal rhythm of CBT on post-stress day 1 only, when compared with sedentary rats. (E) Stress exposure flattened the diurnal rhythm of REM sleep in sedentary rats only on post-stress day 1, but exercise reduced the stress-induced flattening of the diurnal rhythm in REM sleep. The differences in the diurnal rhythm of REM sleep between exercise and sedentary groups were evident both before stress and until post-stress day 3. (F) Stress exposure flattened the diurnal rhythms of NREM sleep in both groups until post-stress day 2. Exercise attenuated the impact of stress on the flattening of the diurnal rhythm of NREM sleep on post-stress day 1 only, when compared with sedentary rats. Although the effects of stress on flattening the diurnal rhythm of NREM sleep had dissipated in both groups by post-stress day 3, exercising rats had a greater diurnal rhythm in NREM sleep when compared to sedentary rats on post-stress day 3. (G) Consistent with the sleep data, stress exposure flattened the diurnal rhythm of WAKE until post-stress day 2. Exercise also reduced the impact of stress on flattening the diurnal rhythm of WAKE on post-stress day 1 only, when compared with the sedentary group. Abbreviations are as follows: arbitrary units (a.u.), pre-stress baseline (BL), beats per minute (bpm), degrees Celsius (°C), diurnal difference (Diff.) and meters (m). (*p < 0.05 effect of stress compared to baseline values; †p < 0.05 exercise compared to sedentary).

Q1, first quarter of diurnal activity defined between individuals’ wake-up time and go-to-bed time); Q2, second quarter of diurnal activity defined between individuals’ wake-up time and go-to-bed time); Q3, third quarter of diurnal activity defined between individuals’ wake-up time and go-to-bed time); Q4, fourth quarter of diurnal activity defined between individuals’ wake-up time and go-to-bed time); +, outlier; *, p<0.05 compared to the previous quarter; **, p<0.00505 compared to the previous quarter; ***, p<0.00105 compared to the previous quarter.

(A) Diurnal temperature (T) condition of each measurement day. (B) Diurnal relative air humidity (RH) condition of each measurement day. (C) Diurnal vapor pressure deficit (VPD) condition of each measurement day. (D) Diurnal photosynthetically active radiation (PAR) condition of each measurement day. Values represent means ± standard errors (n = 3).