EFFECTS OF HUMAN PREGNANCY ON CARDIAC AUTONOMIC ACTIVITY ABOVE AND BELOW THE VENTILATORY ANAEROBIC THRESHOLD 23

SummaryStudy aim: This investigation examined the cardiac vagal modulation-to-vagal tone ratio and its utility to represent the dose response to accumulated exercise stress in intermittent team sport.Material and methods: Fourteen international calibre female field hockey players training as part of a national team were participants over a three-week period. Exercise stress was expressed through cardiovascular strain using heart rate (HR) dynamics and was quantified as a training load (AU) and time spent exercising above anaerobic threshold (min). Cardiac autonomic activity was examined using heart rate variability; R-R intervals (ms) were collected immediately upon awakening throughout each weekend. The square root of the mean squared differences of successive R–R intervals were individually calculated, and log transformed prior to being averaged (Ln rMSSD) along with the corresponding mean R-R interval length. Multiple linear regression analysis examined the association between cardiac autonomic activity and indices of accumulated exercise stress.Results: Significant inverse associations (95% CI) between the Ln rMSSD:R-R ratio and both training load [r = –0.48 (–0.70: –0.18), p = 0.012] and time spent exercising above anaerobic threshold [r = –0.51 (–0.72 : –0.22), p = 0.006] were observed. The association between mean R-R interval length and Ln rMSSD was not significant [r = 0.05, p = 0.950].Conclusion: The current study demonstrated high intensity exercise, as defined through time spent above anaerobic threshold, displayed a stronger association with the Ln rMSSD:R-R ratio compared to a HR-derived training load when examining the dose response to accumulated intermittent exercise.

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The Health Effects of Mercury on the Cardiac Autonomic Activity According to the Heart Rate Variability

Korean Journal of Occupational and Environmental Medicine ◽

10.35371/kjoem.2008.20.4.302 ◽

2008 ◽

Vol 20 (4) ◽

pp. 302 ◽

Cited By ~ 1

Author(s):

Sinye Lim ◽

Min Cheol Choi ◽

Kee Ock Joh ◽

Domyung Paek

Keyword(s):

Heart Rate ◽

Heart Rate Variability ◽

Health Effects ◽

Autonomic Activity ◽

Cardiac Autonomic Activity

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The Effect of Eight-Week Sprint Interval Training on Aerobic Performance of Elite Badminton Players

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18020638 ◽

2021 ◽

Vol 18 (2) ◽

pp. 638

Author(s):

Haochong Liu ◽

Bo Leng ◽

Qian Li ◽

Ye Liu ◽

Dapeng Bao ◽

...

Keyword(s):

Oxygen Uptake ◽

Anaerobic Threshold ◽

Aerobic Capacity ◽

Interval Training ◽

Lactate Clearance ◽

Aerobic Performance ◽

Sprint Interval Training ◽

Control Groups ◽

Ventilatory Anaerobic Threshold ◽

And Control

This study was aimed to: (1) investigate the effects of physiological functions of sprint interval training (SIT) on the aerobic capacity of elite badminton players; and (2) explore the potential mechanisms of oxygen uptake, transport and recovery within the process. Thirty-two elite badminton players volunteered to participate and were randomly divided into experimental (Male-SIT and Female-SIT group) and control groups (Male-CON and Female-CON) within each gender. During a total of eight weeks, SIT group performed three times of SIT training per week, including two power bike trainings and one multi-ball training, while the CON group undertook two Fartlek runs and one regular multi-ball training. The distance of YO-YO IR2 test (which evaluates player’s ability to recover between high intensity intermittent exercises) for Male-SIT and Female-SIT groups increased from 1083.0 ± 205.8 m to 1217.5 ± 190.5 m, and from 725 ± 132.9 m to 840 ± 126.5 m (p < 0.05), respectively, which were significantly higher than both CON groups (p < 0.05). For the Male-SIT group, the ventilatory anaerobic threshold and ventilatory anaerobic threshold in percentage of VO2max significantly increased from 3088.4 ± 450.9 mL/min to 3665.3 ± 263.5 mL/min (p < 0.05),and from 74 ± 10% to 85 ± 3% (p < 0.05) after the intervention, and the increases were significantly higher than the Male-CON group (p < 0.05); for the Female-SIT group, the ventilatory anaerobic threshold and ventilatory anaerobic threshold in percentage of VO2max were significantly elevated from 1940.1 ± 112.8 mL/min to 2176.9 ± 78.6 mL/min, and from 75 ± 4% to 82 ± 4% (p < 0.05) after the intervention, which also were significantly higher than those of the Female-CON group (p < 0.05). Finally, the lactate clearance rate was raised from 13 ± 3% to 21 ± 4% (p < 0.05) and from 21 ± 5% to 27 ± 4% for both Male-SIT and Female-SIT groups when compared to the pre-test, and this increase was significantly higher than the control groups (p < 0.05). As a training method, SIT could substantially improve maximum aerobic capacity and aerobic recovery ability by improving the oxygen uptake and delivery, thus enhancing their rapid repeated sprinting ability.

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Sleep Indices and Cardiac Autonomic Activity Responses during an International Tournament in a Youth National Soccer Team

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18042076 ◽

2021 ◽

Vol 18 (4) ◽

pp. 2076

Author(s):

Pedro Figueiredo ◽

Júlio Costa ◽

Michele Lastella ◽

João Morais ◽

João Brito

Keyword(s):

Heart Rate ◽

Frequency Domain ◽

Sleep Duration ◽

Time Domain ◽

Soccer Players ◽

Autonomic Activity ◽

Male Youth ◽

Youth Soccer ◽

Wrist Actigraphy ◽

Cardiac Autonomic Activity

This study aimed to describe habitual sleep and nocturnal cardiac autonomic activity (CAA), and their relationship with training/match load in male youth soccer players during an international tournament. Eighteen elite male youth soccer players (aged 14.8 ± 0.3 years; mean ± SD) participated in the study. Sleep indices were measured using wrist actigraphy, and heart rate (HR) monitors were used to measure CAA during night-sleep throughout 5 consecutive days. Training and match loads were characterized using the session-rating of perceived exertion (s-RPE). During the five nights 8 to 17 players slept less than <8 h and only one to two players had a sleep efficiency <75%. Players’ sleep duration coefficient of variation (CV) ranged between 4 and 17%. Nocturnal heart rate variability (HRV) indices for the time-domain analyses ranged from 3.8 (95% confidence interval, 3.6; 4.0) to 4.1 ln[ms] (3.9; 4.3) and for the frequency-domain analyses ranged from 5.9 (5.6; 6.5) to 6.6 (6.3; 7.4). Time-domain HRV CV ranged from 3 to 10% and frequency-domain HRV ranged from 2 to 12%. A moderate within-subjects correlation was found between s-RPE and sleep duration [r = −0.41 (−0.62; −0.14); p = 0.003]. The present findings suggest that youth soccer players slept less than the recommended during the international tournament, and sleep duration was negatively associated with training/match load.

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