Age-related differences in post-exercise recovery following high-intensity exercise in masters and young cyclists

The purpose of this thesis and associated series of studies was to compare the acute (1 hrs) in well-trained masters and young cyclists following a high-intensity interval training bout (HIT). The thesis comprises of five manuscripts. Manuscript 1 in Chapter 2 is a narrative literature review published in the Journal of Aging and Physical Activity which examines the significance of the masters athlete population, the importance of recovery for athletes, and the effect of age on recovery following exercise. Manuscripts 2-4 in Chapters 3- 5 investigate age-related differences in acute physiological recovery parameters and Manuscript 5 in Chapter 6 examines differences in chronic parameters of recovery

A comparison of heart rate training load and perceptual effort between masters and young cyclists

Doering, TM ORCiD: 0000-0002-6427-1067; Scanlan, AT ORCiD: 0000-0002-0750-8697Purpose: Due to age-related changes in the psychobiological state of masters athletes, this brief report aimed to compare training load responses using heart rate (HR) and ratings of perceived exertion (RPE) during standardized training sessions between masters and young cyclists. Methods: Masters (n = 10; 55.6 [5.0] y) and young (n = 8; 25.9 [3.0] y) cyclists performed separate endurance and high-intensity interval training sessions. Endurance intensity was set at 95% of ventilatory threshold 2 for 1 hour. High-intensity interval training consisted of 6 × 30-second intervals at 175% peak power output with 4.5-minute rest between intervals. HR was monitored continuously and RPE collected at standardized time periods during each session. Banister training impulse and summated-HR-zones training loads were also calculated. Results: Despite a significantly lower mean HR in masters cyclists during endurance (P = .04; d = 1.06 [±0.8], moderate) and high-intensity interval training (P = .01; d = 1.34 [±0.8], large), no significant differences were noted (P > .05) when responses were determined relative to maximum HR or converted to training impulse and summated-HR-zone loads. Furthermore, no interaction or between-group differences were evident for RPE across either session (P > .05). Conclusions: HR and RPE values were comparable between masters and young cyclists when relative HR responses and HR training load models are used. This finding suggests HR and RPE methods used to monitor or prescribe training load can be used interchangeably between masters and young athletes irrespective of chronological age

Hydration status of rugby union players in hot and humid conditions: a comparative team case study of day and night training sessions

Hydration responses of rugby union players within and between day and night training sessions in hot and humid conditions were monitored. Body mass, fluid ingestion, perceptual thermal stress (TSS) and thirst scores were monitored in ten players (age: 21.9±4.4 years; body mass: 97.9±15.5kg; height: 179.5±5.6cm) across both training sessions. Heat index was higher during the day session compared to the night (44ºC vs 34ºC respectively). Significant interaction effects were found for body mass and TSS. Between-group comparisons revealed no significant fluctuations of body mass between sessions. Temporal comparisons showed a significant reduction in body mass across the night session (97.2±15.7; 96.4±15.4 kg), although the mean decrease in body mass did not exceeded >2%. TSS increased significantly across both day (1.2±1.3; 5.2±1.0) and night sessions (1.4±1.0; 3.6±1.6). However, TSS was significantly higher post-training in the day session and players ingested more fluids during the day session (1.4±0.5; 0.9±0.4 L·hr-1). Reduced thermal stress scores may compromise self-mediated hydration practices in rugby players when training at night and lead to greater body mass loss.Keywords: Fluid balance; Thermal stress; Body mass; Diurnal trainin

Development of a twenty20 field-based simulation for cricket fast bowlers (FBS-T20)

Milne, EC, Vickery, WM, Dascombe, BJ, and Borges, NR. Development of a twenty20 field-based simulation for cricket fast bowlers (FBS-T20). J Strength Cond Res 36(10): 2905-2911, 2022 - This project assessed the validity and reliability of a novel Twenty20 cricket pace bowling simulation (FBS-T20) that could be used to facilitate match-specific testing and training outside of match play. Six recreational pace bowlers completed 3 identical sessions of the FBS-T20. The FBS-T20 consisted of 4 bowling and 16 fielding overs. During the bowling overs, a bowling accuracy test and bowling approach speed were measured, whereas during the fielding overs, 10-m sprint performance was assessed. Distance covered, heart rate (HR), and rating of perceived exertion (RPE) were also collected throughout the FBS-T20. Validity was determined through comparison with previously reported Twenty20 pace bowling match demands, and intersession reliabilities were assessed. Distances covered in speed zones were valid (p > 0.05) with the exception of significantly lower jog values in the FBS-T20 (957-1,279 vs. 2,195 m; p = 0.04-<0.001). The maximal HR was found to be valid, but the mean HR was significantly higher than previously published data (147-151 bpm vs. 133 bpm; p = 0.014-0.003). Distances covered demonstrated high levels of reliability, with increasing reliability found after additional sessions (coefficient of variation [CV]% = 3.8-14.4). The HR (CV% = 4.8-6.3) and session RPE (CV% = 10.8) demonstrated moderate reliability, whereas approach speed, 10-m sprint, and bowling skills test results possessed low levels of reliability. The FBS-T20 is a practically viable testing and training tool that is valid and reliable for distances covered at high speeds. One full familiarization session is recommended for optimal reliability

Blood lactate accumulation and clearance during typical training sessions in well-trained masters and young cyclists

This study compared blood lactate accumulation and clearance in masters (n = 10; age: 56 ± 5 years) and young (n = 8; age: 26 ± 3 years) cyclists during, and following, a continuous cycle (CON) and a high-intensity interval cycle session (HIT). CON was set at an intensity of 95% of ventilatory threshold 2 for one hour. HIT consisted of 6 x 30 second intervals at 175% peak power output with 4.5 minutes rest between intervals. Blood lactate was measured at regular intervals during each protocol and at 5-minute intervals throughout the 20-minute passive recovery period. No significant between-group differences were found for baseline, peak, or end of exercise blood lactate during either protocol (P > 0.05). Following both protocols, the masters cyclists exhibited a higher final blood lactate value (CON: d ± 90%CI = -0.97 ± 0.80, moderate; HIT: d = -0.70 ± 0.81, moderate) and a lower percent change (CON: d = -0.84 ± 0.87, moderate; HIT: d = -0.70 ± 0.85, moderate) during recovery. To mitigate any influence of masters athletes’ diminished blood lactate clearance, it is recommended that extra recovery time or active recovery strategies be used in masters athletes following exercise

The effect of higher than recommended protein feedings post-exercise on recovery following downhill running in masters triathletes

Following exercise-induced muscle damage (EIMD), masters athletes take longer to recover than younger athletes. The purpose of this study was to determine the effect of higher than recommended postexercise protein feedings on the recovery of knee extensor peak isometric torque (PIT), perceptions of recovery, and cycling time trial (TT) performance following EIMD in masters triathletes. Eight masters triathletes (52 ?} 2 y, V?O2max, 51.8 ?} 4.2 ml•kg-1•min-1) completed two trials separated by seven days in a randomized, doubleblind, crossover study. Trials consisted of morning PIT testing and a 30-min downhill run followed by an eight-hour recovery. During recovery, a moderate (MPI; 0.3 g•kg-1•bolus-1) or high (0.6 g•kg-1•bolus-1) protein intake (HPI) was consumed in three bolus feedings at two hour intervals commencing immediately postexercise. PIT testing and a 7 kJ•kg-1 cycling TT were completed postintervention. Perceptions of recovery were assessed pre-And postexercise. The HPI did not significantly improve recovery compared with MPI (p > .05). However, comparison of within-Treatment change shows the HPI provided a moderate beneficial effect (d = 0.66), attenuating the loss of afternoon PIT (-3.6%, d = 0.09) compared with the MPI (-8.6%, d = 0.24). The HPI provided a large beneficial effect (d = 0.83), reducing perceived fatigue over the eight-hour recovery (d = 1.25) compared with the MPI (d = 0.22). Despite these effects, cycling performance was unchanged (HPI = 2395 ?} 297 s vs. MPI = 2369 ?} 278 s; d = 0.09). In conclusion, doubling the recommended postexercise protein intake did not significantly improve recovery in masters athletes; however, HPI provided moderate to large beneficial effects on recovery that may be meaningful following EIMD