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- Ahokas, Essi, et al.
(författare)
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Menstruation has no effect on heart rate variability and subjective sleep quality of physically active women
- 2021
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- INTRODUCTION:Subjective sleep quality may decrease during menstruation, although the duration and composition of sleep remains relatively stable across the menstrual cycle (MC) (1). Recording heart rate variability (HRV) is a tool to monitor the autonomic nervous system and recovery of the body. Meta-analytical data has not revealed significant changes in HRV from the early follicular phase (menses) to the mid-follicular phase (2). However, reduced HRV-values were observed during menses compared to follicular phase in women with pain during menses (dysmenorrhea) (3). Only a few studies have examined effects of the MC on nocturnal HRV. The aim of this study was to investigate how menses and associated pain affects nocturnal HRV and subjective sleep quality.METHODS:Participants included 14 healthy, physically active women, who did not use hormonal contraception. During one MC, participants completed a diary of sleep, MC and related symptoms. HRV was registered every night (Bodyguard 2, Firstbeat Technologies Ltd., Finland). HRV-data (RMSSD and LF/HF-ratio) were analyzed for two nights after a blood sample and over a four-hour period beginning 30 min after bedtime. Only the menses (M) and mid-follicular phases (FP) are used in this study. Blood samples (estradiol, E2, and progesterone, P4) were collected during M (day 2-3 of the MC) and FP (day 7-10) to ensure normal hormonal function associated with the MC (4).RESULTS:E2 was higher (p=0.012) during FP (267±150 pmol/L) compared to M (143±88 pmol/L), but P4 remained stable (p=0.103). Mean heart rate (HRmean) was higher during M (54±8 beats/min) compared to FP (52±7 beats/min, p=0.022). However, HRV-variables did not differ between M and FP (RMSSD: 76.7±34.5 to 77.3±27.0 ms, p=0.872; LF/HF: 1.416±1.380 to 1.273±0.769, p=0.826). Subjectively-assessed sleep quality remained unchanged between M and FP (p=0.349). The change in RMSSD and HRmean between M and FP did not differ (RMSSD: p=0.728; HRmean: p=0.149) between participants with and without menstrual pains.CONCLUSION:Menses has no effect on nocturnal HRV and subjective sleep quality of physically active women, though the higher nocturnal HRmean during M may indicate decreased recovery during menses.REFERENCES:1. Driver, H.S., Werth, E., et al. The Menstrual Cycle Effects on Sleep. Sleep Med Clin 2008, 3:1–11.2. Schmalenberger, K.M., Eisenlohr-Moul, T.M., et al. A Systematic Review and Meta-Analysis of Within-Person Changes in Cardiac Vagal Activity across the Menstrual Cycle: Implications for Female Health and Future Studies. J Clin Med 2019, 8:1946.3. Jayamala, A.K., Preethi, B.L., et al. Comparative Analysis of Heart Rate Variability During Different Phases of Menstrual Cycle in Eumenorrhea & Dysmenorrhea Subjects. Exp Clin Physiol Biochem 2017, 1.4. Elliot-Sale, K.J., Minahan, C.L., et al. Methodological Considerations for Studies in Sport and Exercise Science with Women as Participants: A Working Guide for Standards of Practice for Research on Women. Sports Med 2021, 51:843–861.
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| 2. |
- Taipale, Ritva S., et al.
(författare)
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Cold-water immersion combined with active recovery is equally as effective as active recovery during 10 weeks of high-intensity combined strength and endurance training in men
- 2019
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Ingår i: Biomedical Human Kinetics. - : Walter de Gruyter GmbH. - 2080-2234. ; 11:1, s. 189-192
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Tidskriftsartikel (refereegranskat)abstract
- Study aim: The purpose of this study was to compare the effects of cold-water immersion (CWI) vs. active recovery performed after each individual strength and endurance training session over a 10-week period of high-intensity combined strength and endurance training. Materials and methods: Seventeen healthy men completed 10 weeks of high-intensity combined strength and endurance training. One group (AR, n = 10) completed active recovery that included 15 minutes of running at 30-40% VO2max after every strength training session while the other group (CWI, n = 7) completed 5 minutes of active recovery (at the same intensity as the AR group) followed by 10 minutes of cold-water (12 +/- 1 degrees C) immersion. During CWI, the subjects were seated passively during the 10 minutes of cold-water immersion and the water level remained just below the pectoral muscles. Muscle strength and power were measured by isometric bilateral, 1 repetition maximum, leg press (ISOM LP) and countermovement jump (CMJ) height. Endurance performance was measured by a 3000 m running time trial. Serum testosterone, cortisol, and IGF-1 were assessed from venous blood samples. Results: ISOM LP and CMJ increased significantly over the training period, but 3000 m running time increased only marginally. Serum testosterone, cortisol, and IGF-1 remained unchanged over the intervention period. No differences between the groups were observed. Conclusions: AR and CWI were equally effective during 10 weeks of high-intensity combined strength and endurance training. Thus, physically active individuals participating in high-intensity combined strength and endurance training should use the recovery method they prefer.
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