Inducing low energy availability in trained endurance male athletes results in poorer explosive power

Abstract Purpose Low energy availability in males needs more original research to understand its health and performance consequences. The aim of the study was to induce low energy availability in previously healthy male endurance athletes by reducing energy availability by 25% for 14 consecutive days and measure any potential changes in performance, health, mental state or energy markers. Methods Energy availability was reduced in 12 trained, well-trained and elite endurance athletes by increasing energy expenditure and controlling energy intake. After intervention, health was assessed by blood draw, body composition was measured, energy markers by measuring resting energy expenditure, performance with three specific tests (measuring endurance, agility and explosive power) and two questionnaires were used for psychological assessment (the Three Factor Eating Questionnaire and Well-being questionnaire). Results Reduced energy availability (22.4 ± 6.3 kcal/kg FFM/day) caused significantly lower haemoglobin values (t(12) = 2.652, p = 0.022), there was a tendency for lower iron and IGF-1 (p = 0.066 and p = 0.077, respectively). Explosive power was reduced (t(12) = 4.570, p = 0.001), lactate metabolism was altered and athletes reported poorer well-being (t(12) = 2.385, p = 0.036). Cognitive restriction was correlated with energy availability (r = 0.528, p = 0.039). Conclusion This is the first research providing direct evidence that suboptimal energy availability negatively impacts explosive power before hormonal changes occur in male endurance athletes. It is also the first to show direct association of low energy availability and higher cognitive restriction. We also observed worse well-being and lower haemoglobin values. 25% of energy availability reduction as not enough to elicit changes in resting energy expenditure.

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Measuring Energy Availability and Energy Conservation in Endurance Athletes in the Pre-Race Period

10.21203/rs.3.rs-116741/v1 ◽

2020 ◽

Author(s):

Iva Jurov ◽

Nicola Keay ◽

Vedran Hadžić ◽

Darjan Spudić ◽

Samo Rauter

Keyword(s):

Energy Expenditure ◽

Energy Conservation ◽

Resting Energy Expenditure ◽

Psychological Evaluation ◽

Endurance Athletes ◽

Energy Availability ◽

Male Athletes ◽

Cognitive Restriction ◽

Disordered Eating Patterns ◽

Resting Energy

Abstract Background: Low energy availability in male athletes has gained a lot of attention in the last years, but direct evidence of its effects on health and performance is lacking. Aim of this research was to objectively measure energy availability (EA) in healthy male endurance athletes without pre-existing relative energy deficiency signs during pre-race season. Methods: 12 trained endurance athletes (performance level 3, 4 and 5) participated in the cross-sectional controlled laboratory study. Fat free mass, exercise energy expenditure and energy intake were measured to calculate EA. Resting energy expenditure was measured and estimated to assess energy conservation. Three specific performance tests were used to assess endurance, agility and explosive strength performance. For psychological evaluation, the Three Factor Eating Questionnaire and a short Well-being questionnaire were completed.Results: Mean EA was 29.5 kcal/kg FFM/day. The majority (66.6%) had EA under the threshold for low EA in females. Critical cognitive restriction (≥13) was reported by 75% of participants. There were no differences in performance, blood values or psychological evaluation when subjects were divided into two groups divided by EA=30kcal/kg FFM/day. Cognitive restriction was negatively associated with measured resting energy expenditure and energy conservation (r=-.578, p=.025 and r=-.549, p=.032, respectively).Conclusions: The mean EA measured in this study supports the theory that the threshold for low EA in endurance male athletes might be under the threshold for females. In addition, we confirmed cognitive restriction could be useful for early detection of energy conservation. The high cognitive restriction as measured in our sample stressed the need of eating behavior screening in endurance athletes in order to reduce risk of any disordered eating patterns.

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Relationship between energy availability, energy conservation and cognitive restraint with performance measures in male endurance athletes

Journal of the International Society of Sports Nutrition ◽

10.1186/s12970-021-00419-3 ◽

2021 ◽

Vol 18 (1) ◽

Author(s):

Iva Jurov ◽

Nicola Keay ◽

Vedran Hadžić ◽

Darjan Spudić ◽

Samo Rauter

Keyword(s):

Energy Expenditure ◽

Energy Conservation ◽

Resting Energy Expenditure ◽

Psychological Evaluation ◽

Endurance Athletes ◽

Energy Availability ◽

Male Athletes ◽

Cognitive Restraint ◽

Disordered Eating Patterns ◽

Resting Energy

Abstract Background Low energy availability in male athletes has gained a lot of attention in recent years, but direct evidence of its effects on health and performance is lacking. The aim of this research was to objectively measure energy availability (EA) in healthy male endurance athletes without pre-existing relative energy deficiency signs during pre-race season. Methods Twelve trained endurance athletes (performance level 3, 4, and 5) participated in the cross-sectional controlled laboratory study. Fat-free mass, exercise energy expenditure, and energy intake were measured to calculate EA. Resting energy expenditure was measured and estimated to assess energy conservation. Three specific performance tests were used to assess endurance, agility, and explosive strength performance. For psychological evaluation, the Three Factor Eating Questionnaire and a short Well-being questionnaire were completed. Results Mean EA was 29.5 kcal/kg FFM/day. The majority (66.6%) had EA under the threshold for low EA in females. Critical cognitive restraint (≥13) was reported by 75% of participants. There were no differences in performance, blood values, or psychological evaluation when subjects were divided into two groups divided by EA = 30 kcal/kg FFM/day. Cognitive restraint was negatively associated with measured resting energy expenditure and energy conservation (r = −.578, p = .025 and r = −.549, p = .032, respectively). Conclusions The mean EA measured in this study supports the theory that the threshold for low EA in endurance male athletes might be under the threshold for females. In addition, we confirmed cognitive restraint could be useful for early detection of energy conservation. The high cognitive restraint as measured in our sample stressed the need of eating behavior screening in endurance athletes in order to reduce risk of any disordered eating patterns.

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A Proposal for a Standardized Approach to Inducing Low Energy Availability in Athletes

Applied Sciences ◽

10.3390/app11156679 ◽

2021 ◽

Vol 11 (15) ◽

pp. 6679

Author(s):

Iva Jurov ◽

Nicola Keay ◽

Vedran Hadžić ◽

Samo Rauter

Keyword(s):

Well Being ◽

Low Energy ◽

Critical Duration ◽

Future Research ◽

Research Approach ◽

Energy Availability ◽

Negative Effects ◽

Future Research Directions ◽

And Performance ◽

Low Energy Availability

Low energy availability in athletes is an insufficiently researched phenomenon due to lack of a universal methodology. Current objective and subjective methods for assessing low energy availability lack in accuracy, are not used with a standardized approach and fail to provide comparable, consistent results. Research in male athletes is even more challenging than in females. It is still not known what the threshold for low energy availability is when negative effects on health and performance occur. This is why in this paper a two-way standardized, systematic and controlled protocol for inducing low energy availability in free-living athletes is proposed. Ways of inducing low energy availability in athletes are described with a systematic approach to ensure accurate results. We suggest this is how new tools for assessing low energy availability can be developed with less burden on the athlete and the scientist. Analysis of each proposed protocol provides a rationale for their use. Future research directions are suggested for determining the threshold for low energy availability and determining the critical duration for its negative effects. Finally, we suggest a practical outcome of using the proposed research approach for health practitioners and coaches in order to protect athlete’s well-being.

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Severe Reduction of Energy Availability in Controlled Conditions Causes Poor Endurance Performance, Impairs Explosive Power and Affects Hormonal Status in Trained Male Endurance Athletes

Applied Sciences ◽

10.3390/app11188618 ◽

2021 ◽

Vol 11 (18) ◽

pp. 8618

Author(s):

Iva Jurov ◽

Nicola Keay ◽

Samo Rauter

Keyword(s):

Power Output ◽

Endurance Performance ◽

Well Being ◽

Endurance Athletes ◽

Energy Availability ◽

Eating Behaviours ◽

Explosive Power ◽

Controlled Conditions ◽

Exercise Energy Expenditure ◽

Psychological Questionnaires

The aim of this study was to severely reduce energy availability (EA) in controlled conditions in trained male endurance athletes to observe any effects on health, performance, and psychological and energy markers. EA was reduced by 50% over 14 days in athletes by maintaining identical energy intake and increasing exercise energy expenditure. Blood was drawn, performance was measured by three specific tests (endurance, explosive power and agility) and two psychological questionnaires were used. Reduced EA (17.3 ± 5.0 kcal/kg FFM/day) resulted in lower body fat% (t(12) = 3.36, p = 0.006), lower power output and relative power output (t(12) = 2.69, p = 0.021 t(12) = 2.34, p = 0.036), explosive power was reduced (t(12) = 6.41, p = 0.000), lactate metabolism was altered (p = 0.001). EA was negatively correlated with haemoglobin and testosterone (r = −0.557, p = 0.30 and r = −0.532, p = 0.037), anaerobic threshold (r = −0.597, p = 0.02) and respiratory compensation point (r = −0.575, p = 0.025). There were significant differences in Well-being (t(12) = 4.11, p = 0.002) and the Three Factor Eating Questionnaire (t(12) = −2.71, p = 0.020). This is the first study to demonstrate that endurance performance and explosive power can be affected before detrimental health effects occur in male athletes. Drastic reductions of EA could lead to poor eating behaviours. The two psychological questionnaires seem to be more sensitive to EA changes than blood markers.

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Low Energy Availability and Relative Energy Deficiency in Sport: What Coaches Should Know

International Journal of Sports Science & Coaching ◽

10.1177/17479541211054458 ◽

2022 ◽

pp. 174795412110544

Author(s):

Braeden T. Charlton ◽

Sara Forsyth ◽

David C. Clarke

Keyword(s):

Energy Expenditure ◽

Female Athlete ◽

Relative Energy ◽

Low Energy ◽

Energy Availability ◽

Female Athlete Triad ◽

Energy Deficiency ◽

Research Findings ◽

And Performance ◽

Low Energy Availability

The Female Athlete Triad (Triad) and the more encompassing Relative Energy Deficiency in Sport (RED-S) are disorders caused by low energy availability (LEA). LEA is a state of insufficient energy intake by an athlete relative to their energy expenditure. Persistent LEA results in the deleterious consequences to health and performance that comprise RED-S. With respect to both the Triad and RED-S, researchers have called for more education of those involved with sport, particularly coaches, to help reduce the incidence of these disorders. Recent studies have shown that as few as 15% of coaches are aware of the Triad, with up to 89% unable to identify even one of its symptoms. RED-S is a more recently established concept such that coach knowledge regarding it has only begun to be assessed, but the results of these initial studies indicate similar trends as for the Triad. In this review, we synthesize research findings from 1986 to 2021 that pertains to LEA and RED-S, which coaches should know so they can better guide their athletes.

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Low Energy Availability And The Female Athlete Triad In Endurance Athletes Versus Controls

Medicine & Science in Sports & Exercise ◽

10.1249/01.mss.0000402874.03257.82 ◽

2011 ◽

Vol 43 (Suppl 1) ◽

pp. 68 ◽

Cited By ~ 1

Author(s):

Jade Garneau-Fournier ◽

Nanna Meyer ◽

Andrew Subudhi ◽

Jacqueline Berning

Keyword(s):

Female Athlete ◽

Low Energy ◽

Endurance Athletes ◽

Energy Availability ◽

Female Athlete Triad ◽

Low Energy Availability

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Markers of Energy Metabolism Affect Lactate Metabolism and Aerobic Performance in Competitive Female Cyclists

Applied Sciences ◽

10.3390/app10217563 ◽

2020 ◽

Vol 10 (21) ◽

pp. 7563

Author(s):

Iva Jurov ◽

Vedran Hadžić ◽

Samo Rauter

Keyword(s):

Energy Balance ◽

Anaerobic Capacity ◽

Resting Energy Expenditure ◽

Relative Energy ◽

Low Energy ◽

Aerobic Performance ◽

Energy Availability ◽

Competitive Cyclists ◽

Low Energy Availability ◽

Incremental Testing

(1) Background: Low energy availability (LEA) has negative effects on performance, but mechanisms, timing, and other circumstances of these effects are not yet established. We aim to assess the performance-related effects of low energy availability in competitive female cyclists with a detailed approach to within-day energy availability (WDEB). (2) Methods: Female competitive cyclists (n = 8) completed the measurement of body composition, resting energy expenditure, and incremental testing; they reported diary logs and used accelerometers for energy availability (EA) calculation. Based on the Low Energy Availability in Females (LEAF) questionnaire, performance and energy parameters were compared between cyclists with risk for relative energy deficiency in sport (RED-S; the LEAF+ group) and cyclists without any risk (LEAF−). (3) Results: 87.5% had EA <30 kcal/kg. EA and energy balance in LEAF– were significantly different from LEAF+ cyclists (U = 0.00, z = −2.00, p < 0.05 and U = 0.00, z = −2.00, p < 0.05, respectively). We found significant correlations between WDEB−300 and EA (−0.736, p = 0.037) and energy balance (−0.732, p = 0.039). In addition, relative power output was correlated with mRMR/pRMR (−0.763, p = 0.046). (4) Conclusions: This study is the first to show that WDEB−300 in competitive female cyclists is greater in cyclists with risk for RED-S. Increased time in a catabolic state was correlated to worse anaerobic capacity in incremental testing. Measuring mRMR/pRMR might be useful as it was negatively associated with aerobic performance.

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Study protocol: prevalence of low energy availability and its relation to health and performance among female football players

BMJ Open Sport & Exercise Medicine ◽

10.1136/bmjsem-2021-001219 ◽

2022 ◽

Vol 8 (1) ◽

pp. e001219

Author(s):

Jan H Rosenvinge ◽

Marcus Smavik Dasa ◽

Morten Kristoffersen ◽

Gunn Pettersen ◽

Jorunn Sundgot-Borgen ◽

...

Keyword(s):

Energy Expenditure ◽

Energy Intake ◽

Study Protocol ◽

Low Energy ◽

Self Report ◽

Football Players ◽

Energy Availability ◽

Positioning Systems ◽

And Performance ◽

Low Energy Availability

Enduring low energy availability (LEA) is associated with several potentially serious physiological and mental conditions. LEA has been found highly prevalent among female elite athletes within endurance sports, thus hampering athletes’ health and performance. The prevalence and the underpinning risk factors of LEA among female elite football players are less studied. One reason is that the existing self-report measures and technological devices to monitor energy intake and expenditure are inadequately adapted to capture the nature of the physical activity and energy expenditure among football players and are thus inaccurate.The present paper outlines a study protocol addressing the prevalence of LEA, the measurement of LEA and the correlations of LEA in terms of health and performance in female football players. Four studies will be conducted with the following aims (1) to evaluate the accuracy of global positioning systems (GPS)-based devices to monitor energy expenditure with indirect calorimetry as the gold standard, (2) to assess energy intake, quantify energy expenditure and investigate energy availability through self-report instruments, double labelled water (DLW) and GPS monitoring devices, (3) to determine the point prevalence of LEA using self-report instruments, DLW, dual-X-ray-absorptiometry (DXA) to quantify muscle and bone mass distribution and density, and a battery of hormonal analyses, and (4) to explore whether the prevalence of LEA varies across a full football season. Measures covering mental symptoms and psychological resources will be included, and a selection of biological measures derived from study 3.Measurements of DXA and DLW are resource-demanding and will be collected from one professional club (N~20 women). In contrast, the remaining data will be collected from four professional clubs (N~60 women) located in Bergen, the largest city within the Western region of Norway. Overall procedures and biobank storage procedures have been approved for data collection that will end in December 2024.

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Effects of Low Energy Availability on Bone Health in Endurance Athletes and High-Impact Exercise as A Potential Countermeasure: A Narrative Review

Sports Medicine ◽

10.1007/s40279-020-01396-4 ◽

2020 ◽

Author(s):

Mark J. Hutson ◽

Emma O’Donnell ◽

Katherine Brooke-Wavell ◽

Craig Sale ◽

Richard C. Blagrove

Keyword(s):

Bone Health ◽

Bone Structure ◽

High Impact ◽

Low Energy ◽

Endurance Athletes ◽

Energy Availability ◽

Stress Injury ◽

Bone Stress ◽

Impact Exercise ◽

Low Energy Availability

AbstractEndurance athletes expend large amounts of energy in prolonged high-intensity exercise and, due to the weight-sensitive nature of most endurance sports, often practice periods of dietary restriction. The Female Athlete Triad and Relative Energy Deficiency in Sport models consider endurance athletes at high-risk for suffering from low energy availability and associated health complications, including an increased chance of bone stress injury. Several studies have examined the effects of low energy availability on various parameters of bone structure and markers of bone (re)modelling; however, there are differences in findings and research methods and critical summaries are lacking. It is difficult for athletes to reduce energy expenditure or increase energy intake (to restore energy availability) in an environment where performance is a priority. Development of an alternative tool to help protect bone health would be beneficial. High-impact exercise can be highly osteogenic and energy efficient; however, at present, it is rarely utilized to promote bone health in endurance athletes. Therefore, with a view to reducing the prevalence of bone stress injury, the objectives of this review are to evaluate the effects of low energy availability on bone health in endurance athletes and explore whether a high-impact exercise intervention may help to prevent those effects from occurring.

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Prevalence of Low Energy Availability in Competitively Trained Male Endurance Athletes

Medicina ◽

10.3390/medicina55100665 ◽

2019 ◽

Vol 55 (10) ◽

pp. 665 ◽

Cited By ~ 3

Author(s):

Lane ◽

Hackney ◽

Smith-Ryan ◽

Kucera ◽

Registar-Mihalik ◽

...

Keyword(s):

Resting Metabolic Rate ◽

Relative Energy ◽

Low Energy ◽

Endurance Athletes ◽

Risk Level ◽

Future Research ◽

Energy Availability ◽

Energy Deficiency ◽

Cut Points ◽

Low Energy Availability

Background and Objectives: Relative energy deficiency in sport (RED-S) has been introduced as a broad-spectrum syndrome leading to possible dysfunction in numerous physiological systems, driven primarily by low energy availability (EA). Research in females has identified specific EA cut-points indicative of risk level for developing physiological and performance disturbances. Cut-points in males have yet to be evaluated. This study examined the prevalence of low EA in competitive (non-elite), recreationally trained (CRT) male endurance athletes. Materials and Methods: Subjects were 108 CRT (38.6 ± 13.8 y; 12.2 ± 5.4 h/wk training) male endurance athletes (runners, cyclists, triathletes) who completed a descriptive survey online via Qualtrics® and returned 3 day diet and exercise training records. EA was calculated from returned surveys and training records. Resting metabolic rate (RMR) and lean body mass (LBM) were estimated from self-reported survey data. Prevalence of risk group was categorized based on the female cut-points: at risk (AR) ≤30 kcal/kg LBM, moderate risk (MR) = 30–45 kcal/kg LBM, or no risk (NR) ≥45 kcal/kg LBM. Results: In this sample, 47.2% (n = 51) were classified as AR, 33.3% (n = 36) as MR, and 19.4% (n = 21) as NR for low EA. Cyclists had lower EA (26.9 ± 17.4 kcal/kg LBM, n = 45) than runners (34.6 ± 13.3 kcal/kg LBM, n = 55, p = 0.016) and all other sport categories (39.5 ± 19.1 kcal/kg LBM, n = 8, p = 0.037). Conclusions: The findings indicate this sample had a high prevalence of risk for low EA, at 47.2%. Only 19.4% of participants were at no risk, meaning ~80% of participants were at some degree of risk of experiencing low EA. Cyclists were at greater risk in this cohort of low EA, although why this occurred was unclear and is in need of further investigation. Future research should address whether the current female cut-points for low EA are appropriate for use in male populations.

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