Changes in the Objective Measures of Sleep in Association with Menses Among Female Athletes with Poor Subjective Sleep Quality: Female Athletes with Poor Subjective Sleep Quality Have More Sleep Arousals During Menses

Figures & data

Table 1 Subject Characteristics

	Without Poor Subjective Sleep Quality N=32	With Poor Subjective Sleep Quality N=13	P
Age, years	20.3 ± 1.2	20.2 ± 1.1	0.800
Height, cm	162.0 ± 5.5	161.9 ± 6.9	0.969
Weight, kg	55.3 ± 4.7	58.2 ± 7.7	0.135
BMI, kg/m^2	21.1 ± 1.5	22.1 ± 1.5	0.051
Menstrual cycle, days	28.6 ± 4.0	27.2 ± 3.5	0.416
Duration of menses, days	2.7 ± 1.0	2.6 ± 1.0	0.752
Type of sports			0.546
Soccer, %	11 (34.4)	4 (30.8)
Track and field, %	9 (28.1)	3 (23.1)
Kendo, %	7 (21.9)	2 (15.4)
Basketball, %	5 (15.6)	3 (23.1)
Softball, %	0 (0)	1 (7.7)
PSQI score	3.6 ± 1.0	6.9 ± 1.0	<0.001
ESS score	10.1 ± 3.5	10.7 ± 2.6	0.585
% of athletes with sleepiness, %	15 (46.9)	6 (46.2)	0.999

Note: Continuous data are summarized using the mean ± SD.

Abbreviations: BMI, body mass index; PSQI, Pittsburgh Sleep Quality Index; ESS, Epworth Sleepiness Scale.

Table 2 Changes in Objective Measures of Sleep Other Than Arousal Index in Participants with and without Poor Subjective Sleep Quality

	PSQI Category	M1	M2	MF	P for Interaction
TIB, min	<6 (N = 32)	395.6 ± 64.5	357.6 ± 76.5	394.0 ± 77.4	0.812
	≥6 (N = 13)	404.6 ± 57.9	382.9 ± 55.7	408.5 ± 66.4
TST, min	<6 (N = 32)	359.4 ± 62.5	328.9 ± 73.7	365.9 ± 74.6	0.696
	≥6 (N = 13)	350.9 ± 62.9	337.3 ± 60.8	376.5 ± 56.4
SOL, min	<6 (N = 32)	14.3 (16.0)	13.0 (11.8)	11.8 (12.3)	0.353
	≥6 (N = 13)	20.0 (41.8)	25.0 (21.6)	12.0 (19.9)
SE, %	<6 (N = 32)	91.0 ± 6.9	92.0 ± 5.2	93.4 ± 5.2	0.363
	≥6 (N = 13)	86.8 ± 9.9	88.1 ± 8.8	92.6 ± 5.7
WASO, min	<6 (N = 32)	8.8 (12.0)	6.3 (9.0)	6.8 (9.0)	0.157
	≥6 (N = 13)	9.5 (11.6)	12.0 (11.4)	7.0 (7.4)
% of REM sleep, %	<6 (N = 32)	27.4 ± 5.9	26.8 ± 5.6	27.8 ± 4.2	0.568
	≥6 (N = 13)	25.3 ± 8.3	22.9 ± 6.0	26.0 ± 4.0
% of N3 sleep, %	<6 (N = 32)	24.2 ± 8.9	25.1 ± 8.6	24.2 ± 6.5	0.610
	≥6 (N = 13)	24.0 ± 9.8	23.3 ± 7.0	25.4 ± 6.6

Note: Continuous data are summarized using the mean ± SD or median (interquartile range).

Abbreviations: M1/2, 1^st and 2^nd night after menses onset; MF, mid-follicular phase; N3, deep non-REM sleep; REM, rapid eye movement; SE, sleep efficiency; SOL, sleep onset latency; TST, total sleep time; WASO, wake after sleep onset.

Figure 1 Changes in arousal index across M1/2 and MF. The changes in the arousal index across the menstrual cycle in athletes with poor subjective sleep quality differed from those in athletes without poor subjective sleep quality (p = 0.036). In athletes with poor subjective sleep quality, the arousal index was significantly higher at M1 than at MF (p = 0.015 for ANOVA, p = 0.016 for comparison between M1 and MF, p = 0.111 for comparison between M2 and MF, and p > 0.999 for comparison between M1 and M2). In athletes without poor subjective sleep quality, the arousal index was similar across menstrual cycles (p for ANOVA, 0.131; p = 0.531 for comparison between M1 and MF, p > 0.999 for comparison between M2 and MF, and p = 0.147 for comparison between M1 and M2).

Note: Values represent the mean ± SD.

Abbreviations: ANOVA, analysis of variance; M1/2, 1^st and 2^nd night after menses onset; MF, mid-follicular phase.