The influence of menstruation on training schedules in well-trained and elite female mountain bike, road and cyclocross athletes

Female physiology is unique and driven by fluctuations in sex hormones that regulate the menstrual cycle (MC) (Marsh et al., 2002). These hormones present a myriad of mechanisms that may influence physiological systems, potentially implicating exercise performance. However, research exploring the MC in athletes is limited. This study investigated if different phases of the MC influenced training schedules, sleep quality, arousal and alertness in elite female mountain bike, road and cyclocross athletes. The study was approved by Edinburgh Napier University’s ethics committee. Fifteen well-trained (N=7) and elite (N=8) cyclists (age: 29 ± 7.4 years, height: 1.7 ± 0.1m, body mass: 61.9 ± 7.7kg) tracked their MC symptoms, basal body temperature (BBT), body mass, perceived sleep, and psychological measures daily for 3 months. The MC was split into two phases, follicular (FP) and luteal (LP), and participants were provided ovulation kits to identify the phases. Athlete’s BBT was significantly higher (p<0.05) in the LP (0.21ºC, p=0.00, d=0.4). No significant differences in body mass (FP; 61.8 ± 6.0, LP; 61.0 ± 6.6), sleep duration (FP; 8.0 ± 1 hrs, LP; 8.0 ± 1 hrs), perceived sleep quality (FP; 7 (7-7.8), LP; 7 (7-8)), alertness (FP; 6 (5-7), LP; 7 (6-7)) and arousal (FP; 3 (2-5), LP; 3 (2-5)) were observed. Further, no significant differences for any training variables, average heart rate (FP; 128 ± 37 bpm, LP; 128 ± 38 bpm), training load (bTRIMP) (FP; 173.5 ± 148.6 A.U, LP; 189.8 ± 158.3 A.U), average speed (FP; 19.3 ± 15.6 km.hr, LP; 18.8 ± 9.0 km.hr) and rating of perceived exertion (RPE) (FP; 13.2 ± 2.7, LP; 13.4 ± 3.0) were observed. Several limitations of this study included the lack of hormonal verification underpowered, and a larger cohort with an even discipline split is required to determine more significant values. In conclusion, the MC does not influence physiological responses and training variables in well-trained and elite mountain bike, road and cyclocross female athletes

Caffeine ingestion compromises thermoregulation and does not improve cycling time to exhaustion in the heat amongst males

Purpose Caffeine is a commonly used ergogenic aid for endurance events; however, its efficacy and safety have been questioned in hot environmental conditions. The aim of this study was to investigate the effects of acute caffeine supplementation on cycling time to exhaustion and thermoregulation in the heat. MethodsIn a double-blind, randomised, cross-over trial, 12 healthy caffeine-habituated and unacclimatised males cycled to exhaustion in the heat (35 °C, 40% RH) at an intensity associated with the thermoneutral gas exchange threshold, on two separate occasions, 60 min after ingesting caffeine (5 mg/kg) or placebo (5 mg/kg). ResultsThere was no effect of caffeine supplementation on cycling time to exhaustion (caffeine; 28.5 ± 8.3 min vs. placebo; 29.9 ± 8.8 min, P = 0.251). Caffeine increased pulmonary oxygen uptake by 7.4% (P = 0.003), heat production by 7.9% (P = 0.004), whole-body sweat rate by 21% (P = 0.008), evaporative heat transfer by 16.5% (P = 0.006) and decreased estimated skin blood flow by 14.1% (P 0.05). ConclusionThe greater heat production and storage, as indicated by a sustained increase in core temperature, corroborate previous research showing a thermogenic effect of caffeine ingestion. When exercising at the pre-determined gas exchange threshold in the heat, 5 mg/kg of caffeine did not provide a performance benefit and increased the thermal strain of participants

The Influence of Menstruation on Training Schedules in Well-Trained and Elite Female Mountain Bike, Road and Cyclocross Athletes

Female physiology is unique and driven by fluctuations in sex hormones that regulate the menstrual cycle. These hormones present myriad mechanisms that may influence physiological systems, potentially implicating exercise performance. However, research exploring the MC in athletes is limited. This study investigated if training status (well-trained/elite) influenced MC-related symptoms , training schedules, sleep quality, arousal, and alertness of elite and well-trained female mountain bike, road, and cyclocross athletes. Fifteen well-trained (n= 7) and elite (n= 8) cyclists (age: 29 ± 7yrs, height: 1.7 ± 0.1m, body mass: 61.9 ± 7.7kg) tracked their MC symptoms, basal body temperature, body mass, sleep, arousal, and alertness measures daily for three months. The MC was split into two phases, follicular and luteal, and participants were provided ovulation kits to identify the phases. The most reported symptoms were fatigue, bloating, abdominal pain, and cramping. Athletes' BBT was significantly greater (p0.05) in body mass, sleep duration and quality, alertness and arousal were observed between well-trained and elite athletes. Further, no significant differences between statuses for any training variables, average or maximum heart rate, training load (bTRIMP), average or maximum speed, and rate of perceived exertion were observed. The MC did not influence physiological responses and training variables in well-trained and elite mountain bike, road, and cyclocross female athletes. Nevertheless, individual fluctuations were present, and it is recommended that athletes monitor their own MC to optimize training and ultimately performance

Understanding Experience, Knowledge and Perceived Challenges Related to Bra Fit for Sports Participation: A Scoping Review

The breasts are reported as the fourth largest barrier to participation in physical activity (PA). This scoping review provides a comprehensive understanding of experiences, knowledge and challenges relating to bra fit and sports participation. The search strategy was adopted by the Preferred Reporting Items for Scoping Reviews (PRISMA-ScR) guidelines and multiple databases were searched. All research was in English and within the last 20 years. Exclusion criteria excluded reviews, male participants and the inability to locate or access full-text articles. The JBI critical appraisal tool assessed methodological quality. Twenty-three studies were included. Key themes from the studies are breast motion during PA, sports bra design, perceived barriers to participation in PA and education/knowledge of breast support and bra fit. Increasing breast support reduces breast movement during PA yet breast motion and bra fit are still the most common breast concerns for females. This is likely influenced by poor breast knowledge, leading to poor breast support choices. Future research should explore to what extent breast motion, knowledge and bra fit influences sport participation, and this research should include a more diverse range of adult ages, cup sizes, ethnicities and PA levels to provide a wider and more comprehensive understanding

Caffeine ingestion compromises thermoregulation and does not improve cycling time to exhaustion in the heat among males

Purpose Caffeine is a commonly used ergogenic aid for endurance events; however, its efficacy and safety have been questioned in hot environmental conditions. The aim of this study was to investigate the effects of acute caffeine supplementation on cycling time to exhaustion and thermoregulation in the heat. Methods In a double-blind, randomised, cross-over trial, 12 healthy caffeine-habituated and unacclimatised males cycled to exhaustion in the heat (35 °C, 40% RH) at an intensity associated with the thermoneutral gas exchange threshold, on two separate occasions, 60 min after ingesting caffeine (5 mg/kg) or placebo (5 mg/kg). Results There was no effect of caffeine supplementation on cycling time to exhaustion (caffeine; 28.5 ± 8.3 min vs. placebo; 29.9 ± 8.8 min, P = 0.251). Caffeine increased pulmonary oxygen uptake by 7.4% (P = 0.003), heat production by 7.9% (P = 0.004), whole-body sweat rate by 21% (P = 0.008), evaporative heat transfer by 16.5% (P = 0.006) and decreased estimated skin blood flow by 14.1% (P 0.05). Conclusion The greater heat production and storage, as indicated by a sustained increase in core temperature, corroborate previous research showing a thermogenic effect of caffeine ingestion. When exercising at the pre-determined gas exchange threshold in the heat, 5 mg/kg of caffeine did not provide a performance benefit and increased the thermal strain of participants