ABSTRACT
Purpose: The aim of this study was to investigate and compare the levels of luteinizing hormone (LH), testosterone (T), estradiol (ES), sex hormone-binding globulin (SHBG), and insulin-like growth factor 1 (IGF-1) in master sprint (MS) and master endurance (ME) athletes. Additionally, the possible associations between these hormones, body composition, and lipid profile with athletic performance (% of performance in relation to the current world record) were analyzed. Materials and Methods: The participants were all men: (i) 34 MS (51.0 ± 6.8 years); and (ii) 32 ME (51.7 ± 9.4 years). Student's t-tests for independent samples were performed to compare all variables between groups. Results: MS had a significantly higher (p = .008) average IGF-1 (154.78 ± 29.85 ng/mL) when compared to ME (129.92 ± 25.48 ng/mL). Performance was significantly correlated with IGF-1 (r = 0.424). The MS group had a moderately lower body fat than ME athletes (MS 12.54 ± 4.07 vs. ME 14.60 ± 4.12; p = .078; d = 0.503). Conclusions: Thus, strength/power training exercise/sport seems to be more beneficial for obtaining a higher IGF-1 compared to aerobic/distance exercise/sport. In addition, LH, T, ES, and SHBG were similar between the two groups of athletes and were comparable to the reference values of younger adults.
ABSTRACT
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 (nâ¯=â¯81) were 8 master sprinters (MS; 51.8⯱â¯11.1â¯yrs), 8 master endurance athletes (EN, nâ¯=â¯8, 53.6⯱â¯8.6â¯yrs), 17 age-matched untrained (CON, 47.47⯱â¯6.00â¯yrs) and 48 young controls (YC, 25.40⯱â¯3.87â¯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; pâ¯<â¯.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.
