Reduced Endurance Capacity and Suboptimal Energy Availability in Top-Level Female Cyclists

2020 ◽  
pp. 1-10 ◽  
Author(s):  
Gabriel Barreto ◽  
Luana Farias de Oliveira ◽  
Tiemi Saito ◽  
Rafael Klosterhoff ◽  
Pedro Perim ◽  
...  
Keyword(s):  
Exercise Capacity ◽  
Anaerobic Power ◽  
Time Trial ◽  
Endurance Capacity ◽  
Energy Availability ◽  
Testosterone Concentration ◽  
Stress Markers ◽  
Global Positioning ◽  
And Performance ◽  
Professional Cycling

Purpose: Women’s professional cycling has grown in popularity, and this increase is also apparent in Brazil, which has increased its female cycling calendar in recent years. The aim of this observational study was to (1) determine training and competition loads of a top-level Brazilian female cycling team, (2) evaluate nutrition and clinical health, and (3) measure whether exercise capacity changed throughout the season. Methods: Training and competition data were collected over the season using global positioning system monitors, while laboratory-based physiological and performance measures (incremental cycling test, 30-s Wingate, 4-km time trial) and clinical and nutritional analyses were performed at time points throughout the season. Results: Total distance covered over the year was 11,124 (2895) km (7382–14,698 km). Endurance capacity was reduced over the season (P = .005) but not anaerobic power (all P > .05). Nutrition and stress markers remained largely unchanged throughout the season, although there were some individual fluctuations in some measures, and testosterone concentration was low for some. Median estimated energy availability ranged between 32.3 and 56.8 kcal·kgLBM−1·d−1 during training and 26.4 and 53.8 kcal·kgLBM−1·d−1 during competition. Percentage of training spent in optimal estimated energy availability was generally low, with 3 athletes spending <35% within the optimal intake. Conclusions: Substantial training and competition loads of the monitored professional Brazilian female cyclists may have reduced exercise capacity toward the end of the season, indicative of a grueling yearlong schedule. Several athletes may have had suboptimal energy availability during the season, potentially affecting testosterone concentration. These data demonstrate the difficulties in maintaining optimal nutrition, health, and performance throughout a season in professional female cycling and highlight the need for quality sport-science support for this type of top-level athlete.

scholarly journals The Road to the UCI: Profiling a professional Brazilian female road cycling team

2020 ◽  
Author(s):  
Gabriel Barreto ◽  
Luana Farias de Oliveira ◽  
Tiemi Saito ◽  
Rafael Klosterhoff ◽  
Pedro Perim ◽  
...  
Keyword(s):  
Time Trial ◽  
Energy Availability ◽  
Mineral Density ◽  
Testosterone Levels ◽  
The Road ◽  
Stress Markers ◽  
Road Cycling ◽  
Z Scores ◽  
Total Body ◽  
And Performance

Women’s professional cycling has grown exponentially in popularity in the past years and it has been no different in Brazil. In 2019 the first Brazilian female cycling team achieved UCI ranking status. Nonetheless, there is a paucity of data regarding the seasonal demands that these athletes encounter. This semi-observational study monitored 5 athletes from a Brazilian professional female cycling team throughout their 2018 season, obtaining training and competition data, laboratory-based physiological and performance measures, and clinical and nutritional analyses. Total distance covered over the year was 11124±2895 km (range: 7382 to 14698 km). The athletes competed in 58 races across 5 countries and 3 out of the 5 athletes sustained injuries at different moments throughout the season. Maximal oxygen uptake was reduced over the season (P=0.005), but Wingate and 4-km time-trial performance was unaltered (all P&gt;0.05). All athletes were healthy at the start of the season as demonstrated by the clinical analyses, while all reported regular menstrual cycles; three of the five athletes were taking oral contraceptives. Immunological and haematological parameters were maintained throughout the season and there were few reported cases of infection. Nutritional and stress markers remained largely unchanged throughout the season, although testosterone levels were low for some at various moments. Mean estimated energy availability (EEA) ranged from 32.3 to 56.8 kcal·kgLBM-1·day-1 during training and from 26.4 to 53.8 kcal·kgLBM-1·day-1 during competition. The percent of training spent in optimal EEA was generally low, with three athletes spending less than 35% within the optimal intake. Bone mineral density total body Z-scores ranged from -0.6 to 0.5. Training and competition schedules of these professional Brazilian female cyclists were like those of female World Tour cyclists. Reduced exercise capacity towards the end of the season may be indicative of a gruelling year-long schedule and several of the athletes may have been exposed to sub-optimal energy availability during the season, potentially affecting testosterone levels in several athletes. No further alterations in the hormonal profile, menstrual cycle or incidences of infection were shown. These data demonstrate the complexity of professional female cycling and further longitudinal studies on top-level female cyclists are warranted.

Implementation and Performance Assessment of a Vector Tracking Method Based on a Software GPS Receiver

2011 ◽  
Vol 64 (S1) ◽  
pp. S151-S161 ◽  
Author(s):  
Sihao Zhao ◽  
Mingquan Lu ◽  
Zhenming Feng
Keyword(s):  
Global Positioning System ◽  
Carrier Frequency ◽  
Gps Receiver ◽  
Tracking Loop ◽  
Frequency Tracking ◽  
Tracking Method ◽  
Global Positioning ◽  
Vector Tracking ◽  
Tracking Loops ◽  
And Performance

A number of methods have been developed to enhance the robustness of Global Positioning System (GPS) receivers when there are a limited number of visible satellites. Vector tracking is one of them. It utilizes information from all channels to aid the processing of individual channels to generate receiver positions and velocities. This paper analyzes relationships among code phase, carrier frequency, and receiver position and velocity, and presents a vector loop-tracking algorithm using an Extended Kalman filter implemented in a Matlab-based GPS software receiver. Simulated GPS signals are generated to test the proposed vector tracking method. The results show that when some of the satellites are blocked, the vector tracking loop provides better carrier frequency tracking results for the blocked signals and produces more accurate navigation solutions compared with traditional scalar tracking loops.

scholarly journals Performance Prediction Equation for 2000 m Youth Indoor Rowing Using a 100 m Maximal Test

Biology ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 1082
Author(s):  
Luiz Felipe da Silva ◽  
Paulo Francisco de Almeida-Neto ◽  
Dihogo Gama de Matos ◽  
Steven E. Riechman ◽  
Victor de Queiros ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Reliability Index ◽  
High Reliability ◽  
Low Cost ◽  
Time Trial ◽  
Prediction Equation ◽  
Daily Routine ◽  
Negative Consequences ◽  
Maximum Effort ◽  
And Performance

Background: The exhaustive series of tests undergone by young athletes of Olympic rowing prior to important competitions imply loads of physical stress that can ultimately impact on mood and motivation, with negative consequences for their training and performance. Thus, it is necessary to develop a tool that uses only the performance of short distances but is highly predictive, offering a time expectancy with high reliability. Such a test must use variables that are easy to collect with high practical applicability in the daily routine of coaches. Objective: The objective of the present study was to develop a mathematical model capable of predicting 2000 m rowing performance from a maximum effort 100 m indoor rowing ergometer (IRE) test in young rowers. Methods: The sample consisted of 12 male rowing athletes in the junior category (15.9 ± 1.0 years). A 100 m time trial was performed on the IRE, followed by a 2000 m time trial 24-h later. Results: The 2000 m mathematical model to predict performance in minutes based on the maximum 100 m test demonstrated a high correlation (r = 0.734; p = 0.006), strong reliability index (ICC: 0.978; IC95%: [0.960; 0.980]; p = 0.001) and was within usable agreement limits (Bland -Altman Agreement: −0.60 to 0.60; 95% CI [−0.65; 0.67]). Conclusion: The mathematical model developed to predict 2000 m performance is effective and has a statistically significant reliability index while being easy to implement with low cost.

scholarly journals The Effect of Dietary Nitrate Supplementation on Physiology and Performance in Trained Cyclists

2017 ◽  
Vol 12 (5) ◽  
pp. 684-689 ◽  
Author(s):  
Joseph A. McQuillan ◽  
Deborah K. Dulson ◽  
Paul B. Laursen ◽  
Andrew E. Kilding
Keyword(s):  
Time Trial ◽  
Crossover Design ◽  
Moderate Intensity ◽  
Beetroot Juice ◽  
Double Blind ◽  
Dietary Nitrate ◽  
Performance Time ◽  
Exercise Economy ◽  
Nitrate Supplementation ◽  
And Performance

Purpose:To determine the effect of dietary nitrate (NO3 –) supplementation on physiology and performance in well-trained cyclists after 6–8 d of NO3 – supplementation.Methods:Eight competitive male cyclists (mean ± SD age 26 ± 8 y, body mass 76.7 ± 6.9 kg, VO2peak 63 ± 4 mL · kg–1 · min–1) participated in a double-blind, placebo-controlled, crossover-design study in which participants ingested 70 mL of beetroot juice containing ~4 mmol NO3 – (NIT) or a NO3 –-depleted placebo (PLA), each for 8 d. Replicating pretreatment measures, participants undertook an incremental ramp assessment to determine VO2peak and first (VT1) and second (VT2) ventilatory thresholds on d 6 (NIT6 and PLA6), moderate-intensity cycling economy on d 7 (NIT7 and PLA7), and a 4-km time trial (TT) on d 8 (NIT8 and PLA8).Results:Relative to PLA, 6 d of NIT supplementation produced unclear effects for VO2peak (mean ± 95% confidence limit: 1.8% ± 5.5%) and VT1 (3.7% ± 12.3%) and trivial effects for both VT2 (–1.0% ± 3.0%) and exercise economy on d 7 (–1.0% ± 1.6%). However, effects for TT performance time (–0.7% ± 0.9%) and power (2.4% ± 2.5%) on d 8 were likely beneficial.Conclusions:Despite mostly unclear outcomes for standard physiological determinants of performance, 8 d of NO3 – supplementation resulted in likely beneficial improvements to 4-km TT performance in well-trained male endurance cyclists.

Low energy availability surrogates correlate with health and performance consequences of Relative Energy Deficiency in Sport

2018 ◽  
Vol 53 (10) ◽  
pp. 628-633 ◽  
Author(s):  
Kathryn E Ackerman ◽  
Bryan Holtzman ◽  
Katherine M Cooper ◽  
Erin F Flynn ◽  
Georgie Bruinvels ◽  
...  
Keyword(s):  
Female Athletes ◽  
Relative Energy ◽  
Low Energy ◽  
Clinical Population ◽  
Energy Availability ◽  
Energy Deficiency ◽  
Increased Risk ◽  
Performance Consequences ◽  
And Performance ◽  
Low Energy Availability

Low energy availability (EA) is suspected to be the underlying cause of both the Female Athlete Triad and the more recently defined syndrome, Relative Energy Deficiency in Sport (RED-S). The International Olympic Committee (IOC) defined RED-S as a syndrome of health and performance impairments resulting from an energy deficit. While the importance of adequate EA is generally accepted, few studies have attempted to understand whether low EA is associated with the health and performance consequences posited by the IOC.ObjectiveThe purpose of this cross-sectional study was to examine the association of low EA with RED-S health and performance consequences in a large clinical population of female athletes.MethodsOne thousand female athletes (15–30 years) completed an online questionnaire and were classified as having low or adequate EA. The associations between low EA and the health and performance factors listed in the RED-S models were evaluated using chi-squared test and the odds ratios were evaluated using binomial logistic regression (p<0.05).ResultsAthletes with low EA were more likely to be classified as having increased risk of menstrual dysfunction, poor bone health, metabolic issues, haematological detriments, psychological disorders, cardiovascular impairment and gastrointestinal dysfunction than those with adequate EA. Performance variables associated with low EA included decreased training response, impaired judgement, decreased coordination, decreased concentration, irritability, depression and decreased endurance performance.ConclusionThese findings demonstrate that low EA measured using self-report questionnaires is strongly associated with many health and performance consequences proposed by the RED-S models.

Increased Cardiorespiratory Stress During Submaximal Cycling After Ketone Monoester Ingestion in Endurance-Trained Adults

2021 ◽  
Author(s):  
Devin Goddard McCarthy ◽  
William Bostad ◽  
Fiona Jane Powley ◽  
Jonathan P. Little ◽  
Douglas Richards ◽  
...  
Keyword(s):  
Body Mass ◽  
Ketone Body ◽  
Perceived Exertion ◽  
Bolus Dose ◽  
Ventilatory Threshold ◽  
Time Trial ◽  
Rating Of Perceived Exertion ◽  
Threshold Intensity ◽  
Double Blind ◽  
And Performance

There is growing interest in the effect of exogenous ketone body supplementation on exercise responses and performance. The limited studies to date have yielded equivocal data, likely due in part to differences in dosing strategy, increase in blood ketones, and participant training status. Using a randomized, double-blind, counterbalanced design, we examined the effect of ingesting a ketone monoester (KE) supplement (600 mg/kg body mass) or flavour-matched placebo in endurance-trained adults (n=10 males, n=9 females; VO2peak=57±8 ml/kg/min). Participants performed a 30-min cycling bout at ventilatory threshold intensity (71±3% VO2peak), followed 15 min later by a 3 kJ/kg body mass time-trial. KE versus placebo ingestion increased plasma [β-hydroxybutyrate] before exercise (3.9±1.0 vs 0.2±0.3 mM, p<0.0001, dz=3.4), ventilation (77±17 vs 71±15 L/min, p<0.0001, dz=1.3) and heart rate (155±11 vs 150±11 beats/min, p<0.001, dz=1.2) during exercise, and rating of perceived exertion at the end of exercise (15.4±1.6 vs 14.5±1.2, p<0.01, dz=0.85). Plasma [β-hydroxybutyrate] remained higher after KE vs placebo ingestion before the time-trial (3.5±1.0 vs 0.3±0.2 mM, p<0.0001, dz=3.1), but performance was not different (KE: 16:25±2:50 vs placebo: 16:06±2:40 min:s, p=0.20; dz=0.31). We conclude that acute ingestion of a relatively large KE bolus dose increased markers of cardiorespiratory stress during submaximal exercise in endurance-trained participants. Novelty bullets: •Limited studies have yielded equivocal data regarding exercise responses after acute ketone body supplementation. •Using a randomized, double-blind, placebo-controlled, counterbalanced design, we found that ingestion of a large bolus dose of a commercial ketone monoester supplement increased markers of cardiorespiratory stress during cycling at ventilatory threshold intensity in endurance-trained adults.

scholarly journals Caffeine Supplementation for 4 Days Does Not Induce Tolerance to the Ergogenic Effects Promoted by Acute Intake on Physiological, Metabolic, and Performance Parameters of Cyclists: A Randomized, Double-Blind, Crossover, Placebo-Controlled Study

Nutrients ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 2101
Author(s):  
Anderson Pontes Morales ◽  
Felipe Sampaio-Jorge ◽  
Thiago Barth ◽  
Anna Paola Trindade Rocha Pierucci ◽  
Beatriz Gonçalves Ribeiro
Keyword(s):  
Time Trial ◽  
Minute Volume ◽  
Controlled Study ◽  
Performance Parameters ◽  
Double Blind ◽  
Double Blind Placebo ◽  
Ergogenic Effects ◽  
And Performance ◽  
Experimental Trials ◽  
Acute Intake

The present study investigated whether the caffeine supplementation for four days would induce tolerance to the ergogenic effects promoted by acute intake on physiological, metabolic, and performance parameters of cyclists. A double-blind placebo-controlled cross-over design was employed, involving four experimental trials; placebo (4-day)-placebo (acute)/PP, placebo (4-day)-caffeine (acute)/PC, caffeine (4-day)-caffeine (acute)/CC and caffeine (4-day)-placebo (acute)/CP. Fourteen male recreationally-trained cyclists ingested capsules containing either placebo or caffeine (6 mg∙kg−1) for 4 days. On day 5 (acute), capsules containing placebo or caffeine (6 mg∙kg−1) were ingested 60 min before completing a 16 km time-trial (TT). CC and PC showed improvements in time (3.54%, ES = 0.72; 2.53%, ES = 0.51) and in output power (2.85%, ES = 0.25; 2.53%, ES = 0.20) (p < 0.05) compared to CP and PP conditions, respectively. These effects were accompanied by increased heart rate (2.63%, ES = 0.47; 1.99%, ES = 0.34), minute volume (13.11%, ES = 0.61; 16.32%, ES = 0.75), expired O2 fraction (3.29%, ES = 0.96; 2.87, ES = 0.72), lactate blood concentration (immediately after, 29.51% ES = 0.78; 28.21% ES = 0.73 recovery (10 min), 36.01% ES = 0.84; 31.22% ES = 0.81), and reduction in expired CO2 fraction (7.64%, ES = 0.64; 7.75%, ES = 0.56). In conclusion, these results indicate that caffeine, when ingested by cyclists in a dose of 6 mg∙kg−1 for 4 days, does not induce tolerance to the ergogenic effects promoted by acute intake on physiological, metabolic, and performance parameters.

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