Heart rate variability in middle-aged sprint and endurance athletes.

BACKGROUND: Aging is associated with decreased autonomic balance which could be assessed by Heart Rate Variability (HRV). Exercise training improves autonomic balance, but there is a lack in the literature regarding the heart rate variability (HRV) of master sprinters and endurance athletes. PURPOSE: The effects of lifelong endurance and sprint training on cardiac autonomic balance were assessed in master athletes and compared with age-matched controls and young untrained controls. METHODS: Participants (n = 81) were 8 master sprinters (MS; 51.8 ±â€¯11.1 yrs), 8 master endurance athletes (EN, n = 8, 53.6 ±â€¯8.6 yrs), 17 age-matched untrained (CON, 47.47 ±â€¯6.00 yrs) and 48 young controls (YC, 25.40 ±â€¯3.87 yrs). For the acquisition of RR intervals (iRR) (Polar RS800X Heart Rate Monitor®) the participants remained seated for 15-min with the final 10-min being considered for analysis. HRV was measured using Kubios software. A one-way ANOVA with repeated measures was applied. RESULTS: All studied parameters did not differ between MS and EN {Time Domain [HR (bpm) 59.00 ±â€¯6.13 vs. 58.94 ±â€¯12.75], [R-R (ms) 1030.45 ±â€¯107.45 vs. 1068.77 ±â€¯206.17], [SDNN (ms) 57.35 ±â€¯20.07 vs. 80.66 ±â€¯71.07], [RMSSD (ms) 40.88 ±â€¯20.07 vs. 38.93 ±â€¯20.44]; Non-linear domain [SD1 (ms) 28.93 ±â€¯14.20 vs. 27.56 ±â€¯14.46]}, whose demonstrated a reduced HR and elevated mean R-R intervals in comparison to both YC {[HR (bpm) 69.64 ±â€¯9.81]; [R-R (ms) 883.93 ±â€¯124.11]} and age-matched controls {[HR (bpm) 70.06 ±â€¯6.63]; [R-R (ms) 865.11 ±â€¯78.39]}. It was observed a lower HRV for middle-aged CON {[RMSSD (ms) 20.23 ±â€¯5.87], [SDNN (ms) 37.79 ±â€¯10.15] and [SD1 (ms) 14.31 ±â€¯4.15]} compared to YC {[RMSSD (ms) 43.33 ±â€¯26.41], [SDNN (ms) 67.07 ±â€¯28.77] and [SD1 (ms) 30.66 ±â€¯18.69; p < .05]}. These last age-related differences were not observed for MS and EN. CONCLUSION: For master athletes, regardless of whether they are trained in endurance or sprinters, both training modes revealed to be equally beneficial in attenuating the effects of aging on the autonomic balance.

Effects of short-term plyometric training on physical fitness parameters in female futsal athletes.

[Purpose] To verify the effects of short-term plyometric training (PM) on body composition, flexibility and muscle power output in female Futsal athletes. [Subjects and Methods] Twenty female Futsal athletes (19.5 ± 1.29 years) equally and randomly divided into control and experimental groups were submitted to a sit-and-reach flexibility test, body composition measures and horizontal jump, at baseline and one day after the final training session. Both groups retained their training routines while only the experimental group participated in an additional 25 minutes of PM 2 times a week over 4 weeks. [Results] The experimental group showed higher values of flexibility and muscle power and lower body fat after the intervention in comparison to the baseline and control group. In addition, the effect size within-group after intervention indicated a moderate, large and very large effect for body fat, flexibility and muscle power, respectively. [Conclusion] These results show that plyometric training may be effective in reducing body fat and increasing flexibility and muscle power in female Futsal athletes. Thus, it may suggest that PM can be applied in the field of preventive physical therapy.