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Anna Melin, Monica Klungland Torstveit, Louise Burke, Saul Marks and Jorunn Sundgot-Borgen

Disordered eating behavior (DE) and eating disorders (EDs) are of great concern because of their associations with physical and mental health risks and, in the case of athletes, impaired performance. The syndrome originally known as the Female Athlete Triad, which focused on the interaction of energy availability, reproductive function, and bone health in female athletes, has recently been expanded to recognize that Relative Energy Deficiency in Sport (RED-S) has a broader range of negative effects on body systems with functional impairments in both male and female athletes. Athletes in leanness-demanding sports have an increased risk for RED-S and for developing EDs/DE. Special risk factors in aquatic sports related to weight and body composition management include the wearing of skimpy and tight-fitting bathing suits, and in the case of diving and synchronized swimming, the involvement of subjective judgments of performance. The reported prevalence of DE and EDs in athletic populations, including athletes from aquatic sports, ranges from 18 to 45% in female athletes and from 0 to 28% in male athletes. To prevent EDs, aquatic athletes should practice healthy eating behavior at all periods of development pathway, and coaches and members of the athletes’ health care team should be able to recognize early symptoms indicating risk for energy deficiency, DE, and EDs. Coaches and leaders must accept that DE/EDs can be a problem in aquatic disciplines and that openness regarding this challenge is important.

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Katie J. Thralls, Jeanne F. Nichols, Michelle T. Barrack, Mark Kern and Mitchell J. Rauh

Early detection of the female athlete triad is essential for the long-term health of adolescent female athletes. The purpose of this study was to assess relationships between common anthropometric markers (ideal body weight [IBW] via the Hamwi formula, youth-percentile body mass index [BMI], adult BMI categories, and body fat percentage [BF%]) and triad components, (low energy availability [EA], measured by dietary restraint [DR], menstrual dysfunction [MD], low bone mineral density [BMD]). In the sample (n = 320) of adolescent female athletes (age 15.9± 1.2 y), Spearman’s rho correlations and multiple logistic regression analyses evaluated associations between anthropometric clinical cutoffs and triad components. All underweight categories for the anthropometric measures predicted greater likelihood of MD and low BMD. Athletes with an IBW ≤85% were nearly 4 times more likely to report MD (OR = 3.7, 95% CI [1.8, 7.9]) and had low BMD (OR = 4.1, 95% CI [1.2, 14.2]). Those in <5th percentile for their age-specific BMI were 9 times more likely to report MD (OR 9.1, 95% CI [1.8, 46.9]) and had low BMD than those in the 50th to 85th percentile. Athletes with a high BF% were almost 3 times more likely to report DR (OR = 2.8, 95% CI [1.4, 6.1]). Our study indicates that low age-adjusted BMI and low IBW may serve as evidence-based clinical indicators that may be practically evaluated in the field, predicting MD and low BMD in adolescents. These measures should be tested for their ability as tools to minimize the risk for the triad.

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Jeanne F. Nichols, Hilary Aralis, Sonia Garcia Merino, Michelle T. Barrack, Lindsay Stalker-Fader and Mitchell J. Rauh

There is a growing need to accurately assess exercise energy expenditure (EEE) in athletic populations that may be at risk for health disorders because of an imbalance between energy intake and energy expenditure. The Actiheart combines heart rate and uniaxial accelerometry to estimate energy expenditure above rest. The authors’ purpose was to determine the utility of the Actiheart for predicting EEE in female adolescent runners (N = 39, age 15.7 ± 1.1 yr). EEE was measured by indirect calorimetry and predicted by the Actiheart during three 8-min stages of treadmill running at individualized velocities corresponding to each runner’s training, including recovery, tempo, and 5-km-race pace. Repeated-measures ANOVA with Bonferroni post hoc comparisons across the 3 running stages indicated that the Actiheart was sensitive to changes in intensity (p < .01), but accelerometer output tended to plateau at race pace. Pairwise comparisons of the mean difference between Actiheart- and criterion-measured EEE yielded values of 0.0436, 0.0539, and 0.0753 kcal · kg−1 · min−1 during recovery, tempo, and race pace, respectively (p < .0001). Bland–Altman plots indicated that the Actiheart consistently underestimated EEE except in 1 runner’s recovery bout. A linear mixed-model regression analysis with height as a covariate provided an improved EEE prediction model, with the overall standard error of the estimate for the 3 speeds reduced to 0.0101 kcal · kg−1 · min−1. Using the manufacturer’s equation that combines heart rate and uniaxial motion, the Actiheart may have limited use in accurately assessing EEE, and therefore energy availability, in young, female competitive runners.

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Victor Silveira Coswig, David Hideyoshi Fukuda and Fabrício Boscolo Del Vecchio

The purpose of this study was to compare biochemical and hormonal responses between mixed martial arts (MMA) competitors with minimal prefight weight loss and those undergoing rapid weight loss (RWL). Blood samples were taken from 17 MMA athletes (Mean± SD; age: 27.4 ±5.3yr; body mass: 76.2 ± 12.4kg; height: 1.71 ± 0.05m and training experience: 39.4 ± 25 months) before and after each match, according to the official events rules. The no rapid weight loss (NWL, n = 12) group weighed in on the day of the event (~30 min prior fight) and athletes declared not having used RWL strategies, while the RWL group (n = 5) weighed in 24 hr before the event and the athletes claimed to have lost 7.4 ± 1.1kg, approximately 10% of their body mass in the week preceding the event. Results showed significant (p < .05) increases following fights, regardless of group, in lactate, glucose, lactate dehydrogenase (LDH), creatinine, and cortisol for all athletes. With regard to group differences, NWL had significantly (p < .05) greater creatinine levels (Mean± SD; pre to post) (NWL= 101.6 ± 15–142.3 ± 22.9μmol/L and RWL= 68.9 ± 10.6–79.5 ± 15.9μmol/L), while RWL had higher LDH (median [interquartile range]; pre to post) (NWL= 211.5[183–236] to 231[203–258]U/L and RWL= 390[370.5–443.5] to 488[463.5–540.5]U/L) and AST (NWL= 30[22–37] to 32[22–41]U/L and 39[32.5–76.5] to 72[38.5–112.5] U/L) values (NWL versus RWL, p < .05). Post hoc analysis showed that AST significantly increased in only the RWL group, while creatinine increased in only the NWL group. The practice of rapid weight loss showed a negative impact on energy availability and increased both muscle damage markers and catabolic expression in MMA fighters.

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Helen G. Hanstock, Andrew D. Govus, Thomas B. Stenqvist, Anna K. Melin, Øystein Sylta and Monica K. Torstveit

Intensive training periods may negatively influence immune function, but the immunological consequences of specific high-intensity training (HIT) prescriptions are not well defined.

Purpose:

This study explored whether three different HIT prescriptions influence multiple health-related biomarkers and whether biomarker responses to HIT were associated with upper respiratory illness (URI) risk.

Methods:

Twenty-five male cyclists and triathletes were randomised to three HIT groups and completed twelve HIT sessions over four weeks. Peak oxygen consumption (V̇O2peak) was determined using an incremental cycling protocol, while resting serum biomarkers (cortisol, testosterone, 25(OH)D and ferritin), salivary immunoglobulin-A (s-IgA) and energy availability (EA) were assessed before and after the training intervention. Participants self-reported upper respiratory symptoms during the intervention and episodes of URI were identified retrospectively.

Results:

Fourteen athletes reported URIs, but there were no differences in incidence, duration or severity between groups. Increased risk of URI was associated with higher s-IgA secretion rates (odds ratio=0.90, 90% CI:0.83-0.97). Lower pre-intervention cortisol and higher EA predicted a 4% increase in URI duration. Participants with higher V̇O2peak reported higher total symptom scores (incidence rate ratio=1.07, 90% CI:1.01-1.13).

Conclusions:

Although multiple biomarkers were weakly associated with risk of URI, the direction of associations between s-IgA, cortisol, EA and URI risk were inverse to previous observations and physiological rationale. There was a cluster of URIs within the first week of the training intervention, but no samples were collected at this time-point. Future studies should incorporate more frequent sample time-points, especially around the onset of new training regimes, and include athletes with suspected or known nutritional deficiencies.

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Alon Eliakim

Introduction:

Competitive female athletes restrict energy intake and increase exercise energy expenditure frequently resulting in ovarian suppression. The purpose of this study was to determine the impact of ovarian suppression and energy deficit on swimming performance (400-m swim velocity).

Methods:

Menstrual status was determined by circulating estradiol (E2) and progesterone (P4) in ten junior elite female swimmers (15-17 yr). The athletes were categorized as cyclic (CYC) or ovarian-suppressed (OVS). They were evaluated every 2 weeks for metabolic hormones, bioenergetic parameters, and sport performance during the 12-week season.

Results:

CYC and OVS athletes were similar (p > .05) in age (CYC = 16.2 ± 1.8 yr, OVS = 17 ± 1.7 yr), body mass index (CYC = 21 ± 0.4 kg·m, OVS = 25 ± 0.8 kg·m), and gynecological age (CYC = 2.6 ± 1.1 yr, OVS = 2.8 ± 1.5 yr). OVS had suppressed P4 (p < .001) and E2 (p = .002) across the season. Total triiodothyronine (TT3) and insulin-like growth factor (IGF-1) were lower in OVS (TT3: CYC = 1.6 ± 0.2 nmol·L, OVS = 1.4 ± 0.1 nmol·L, p < .001; IGF-1: CYC = 243 ± 1 μg·mL, OVS = 214 μg·mL p < .001) than CYC at week 12. Energy intake (p < .001) and energy availability (p < .001) were significantly lower in OVS versus CYC. OVS exhibited a 9.8% decline in Δ400-m swim velocity compared with an 8.2% improvement in CYC at week 12.

Conclusions:

Ovarian steroids (P4 and E2), metabolic hormones (TT3 and IGF-1), and energy status markers (EA and EI) were highly correlated with sport performance. This study illustrates that when exercise training occurs in the presence of ovarian suppression with evidence for energy conservation (i.e., reduced TT3), it is associated with poor sport performance. These data from junior elite female athletes support the need for dietary periodization to help optimize energy intake for appropriate training adaptation and maximal sport performance

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Margo L. Mountjoy, Louise M. Burke, Trent Stellingwerff and Jorunn Sundgot-Borgen

prevention and treatment programs from IFs all the way down to grassroots sports. The term “RED-S” was coined by the International Olympic Committee in 2014 ( Mountjoy et al., 2014 ), expanding the female athlete triad model to recognize that low energy availability (LEA), which underpins both the triad and

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Margo Mountjoy, Jorunn Sundgot-Borgen, Louise Burke, Kathryn E. Ackerman, Cheri Blauwet, Naama Constantini, Constance Lebrun, Bronwen Lundy, Anna Melin, Nanna Meyer, Roberta Sherman, Adam S. Tenforde, Monica Klungland Torstveit and Richard Budgett

not limited to impairments of metabolic rate, menstrual function, bone health, immunity, protein synthesis, and cardiovascular health.” The aetiological factor of this syndrome is low energy availability (LEA) ( Mountjoy et al., 2014 ). The publication of the RED-S consensus statement stimulated

Open access

Louise M. Burke, Linda M. Castell, Douglas J. Casa, Graeme L. Close, Ricardo J. S. Costa, Ben Desbrow, Shona L. Halson, Dana M. Lis, Anna K. Melin, Peter Peeling, Philo U. Saunders, Gary J. Slater, Jennifer Sygo, Oliver C. Witard, Stéphane Bermon and Trent Stellingwerff

volume requires dietary energy and CHO support, especially for high quality and race practice workouts • High power to weight ratio (i.e., low body mass/fat content) associated with success but poses another risk for low energy availability. • Race success requires high availability of economical CHO

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Samuel G. Impey, Kelly M. Hammond, Robert Naughton, Carl Langan-Evans, Sam O. Shepherd, Adam P. Sharples, Jessica Cegielski, Kenneth Smith, Stewart Jeromson, David L. Hamilton, Graeme L. Close and James P. Morton

exercise, 22 g during exercise, and a further 22 g immediately postexercise. Both trials represented deliberate conditions of reduced CHO and absolute energy availability, but with high protein availability in the form of whey or collagen throughout. Muscle biopsies were obtained from the vastus lateralis