scholarly journals Low Energy Availability with and without a High-Protein Diet Suppresses Bone Formation and Increases Bone Resorption in Men: A Randomized Controlled Pilot Study

Nutrients ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 802
Author(s):  
Chaise Murphy ◽  
Laura D. Bilek ◽  
Karsten Koehler
Keyword(s):  
Bone Resorption ◽  
Bone Turnover ◽  
High Protein Diet ◽  
Low Energy ◽  
High Protein ◽  
Fat Free Mass ◽  
Protein Diet ◽  
Energy Availability ◽  
Serum Samples ◽  
Low Energy Availability

Suppression of insulin-like growth factor 1 (IGF-1) and leptin secondary to low energy availability (LEA) may contribute to adverse effects on bone health. Whether a high-protein diet attenuates these effects has not been tested. Seven men completed three five-day conditions operationally defined as LEA (15 kcal kg fat-free mass (FFM)-1 day-1) with low protein (LEA-LP; 0.8 g protein·kg body weight (BW)-1), LEA with high protein (LEA-HP; 1.7 g protein·kg BW-1) and control (CON; 40 kcal·kg FFM-1·day-1, 1.7 g protein·kg BW-1). In all conditions, participants expended 15 kcal·kg FFM-1·day-1 during supervised cycling sessions. Serum samples were analyzed for markers of bone turnover, IGF-1 and leptin. The decrease in leptin during LEA-LP (-65.6 ± 4.3%) and LEA-HP (-54.3 ± 16.7%) was greater than during CON (-25.4 ± 11.4%; p = 0.02). Decreases in P1NP (p = 0.04) and increases in CTX-I (p = 0.04) were greater in LEA than in CON, suggesting that LEA shifted bone turnover in favour of bone resorption. No differences were found between LEA-LP and LEA-HP. Thus, five days of LEA disrupted bone turnover, but these changes were not attenuated by a high-protein diet.

scholarly journals Do paralympic track and field athletes have low energy availability?

2018 ◽  
Vol 20 (1) ◽  
pp. 71-81 ◽  
Author(s):  
Daniel Paduan Joaquim ◽  
Claudia Ridel Juzwiak ◽  
Ciro Winckler
Keyword(s):  
Body Composition ◽  
Low Energy ◽  
Track And Field ◽  
Fat Free Mass ◽  
Motion Sensor ◽  
Energy Availability ◽  
Energy Demands ◽  
Physiological Processes ◽  
Limb Deficiency ◽  
Low Energy Availability

One of the greatest challenges when working with athletes is to achieve the energy demands for physiological processes and exercise expenditure. The aim of this study was to assess the energy availability (EA) of Paralympic track and field athletes (sprinters). Seventeen athletes (9 male and 8 female) with visual impairment (VI, n=10), cerebral palsy (CP, n=4) and limb deficiency (LD, n=3) were assessed for energy intake (EI) (4-day food photographic record), energy expenditure with exercise (EEex) (motion sensor), and body composition (skinfolds method). Energy availability was estimated using the equation: EA = (EIkcal - EEexkcal) / fat-free mass (FFM) / day, and values ≤ 30kcal/kgFFM/day were considered as low energy availability (LEA). EEex varied from 130 to 477kcal/h and athletes trained in average for 3.2 hours per day. Mean EA for VI, LD and CP were 36 (2.19), 37 (1.90) and 38 (3.38) kcal/kgFFM/day, respectively. Most (82.3%) participants presented EA below ≥ 45kcal/kgFFM/day, throughout the days, which are the recommended values for athletes without disability. Athletes should be encouraged to consume adequate EA to avoid consequences related to low energy availability. There is need of further research to identify cut-off values adequate for this population.

The Effects of Short-Term Low Energy Availability on Bone Turnover in Men

2015 ◽  
Vol 47 ◽  
pp. 414 ◽  
Author(s):  
Maria Papageorgiou ◽  
Kirsty J. Elliott-Sale ◽  
Julie P. Greeves ◽  
William D. Fraser ◽  
Craig Sale
Keyword(s):  
Bone Turnover ◽  
Low Energy ◽  
Energy Availability ◽  
Short Term ◽  
Low Energy Availability

Impaired Bone Turnover In Women, But Not In Men, In Response To Low Energy Availability

2016 ◽  
Vol 48 ◽  
pp. 219
Author(s):  
Maria Papageorgiou ◽  
Kirsty J. Elliott-Sale ◽  
Julie P. Greeves ◽  
William D. Fraser ◽  
Craig Sale
Keyword(s):  
Bone Turnover ◽  
Low Energy ◽  
Energy Availability ◽  
Low Energy Availability

Effect of diets with different energy and protein levels on performance of grower ostriches

2008 ◽  
Vol 48 (10) ◽  
pp. 1338 ◽  
Author(s):  
P. C. Glatz ◽  
Z. H. Miao ◽  
B. K. Rodda ◽  
S. C. Wyatt
Keyword(s):  
High Protein Diet ◽  
High Energy ◽  
Bodyweight Gain ◽  
Low Energy ◽  
High Protein ◽  
Protein Diet ◽  
Daily Weight Gain ◽  
Protein Levels ◽  
Low Protein ◽  
Feed Costs

Grower ostriches that are fed more expensive diets with high energy and high protein to maximise growth can exhibit health problems. Despite this there is an ‘industry view’ that birds can be grown to slaughter weight within 8 months when high energy and protein diets are used, rather than 12–14 months using conventional diets. Given this scenario it is likely that there would be lower total feed costs associated with feeding a high energy and high protein diet for only 8 months compared with feeding a traditional diet for 12–14 months. The purpose of this experiment was to conduct an on-farm trial with grower ostriches (liveweight 48.7–50.0 kg) housed in a feedlot to examine their performance when subjected to four dietary treatments fed over 4 weeks: (i) treatment 1: birds fed a commercial grower diet with 10.7 MJ/kg and 138.0 g/kg of protein; (ii) treatment 2: birds fed a low energy (10.0 MJ/kg) and low protein (126.0 g/kg) diet; (iii) treatment 3: birds fed a high energy (12.5 MJ/kg) and medium protein (136.0 g/kg) diet; and (iv) treatment 4: birds fed a high energy (12.5 MJ/kg) and high protein (143.0 g/kg) diet in a feedlot. Birds fed on the low energy and low protein diet had the highest feed intake compared with the other treatments. Birds on treatment 2 also had a significantly higher (P = 0.01) daily weight gain (277.3 g/bird) compared with treatment 1 (50.9 g), treatment 3 (49.1 g) and treatment 4 (32.0 g), respectively. The results indicate that better daily bodyweight gain is likely if ostrich growers are fed with a lower energy and lower protein diet.

Prevalence of Indicators of Low Energy Availability in Elite Female Sprinters

2018 ◽  
Vol 28 (5) ◽  
pp. 490-496 ◽  
Author(s):  
Jennifer Sygo ◽  
Alexandra M. Coates ◽  
Erik Sesbreno ◽  
Margo L. Mountjoy ◽  
Jamie F. Burr
Keyword(s):  
Blood Pressure ◽  
Fasting Blood Glucose ◽  
Signs And Symptoms ◽  
Relative Energy ◽  
Low Energy ◽  
Fat Free Mass ◽  
Energy Availability ◽  
Mineral Density ◽  
Energy Deficiency ◽  
Low Energy Availability

Low energy availability (LEA), and subsequent relative energy deficiency in sport, has been observed in endurance, aesthetic, and team sport athletes, with limited data on prevalence in athletes in short-burst activities such as sprinting. We examined prevalence of signs and symptoms of LEA in elite female sprinters at the start of the training season (PRE), and at the end of a 5-month indoor training period (POST). Four of 13 female sprinters (31%) presented at PRE testing with at least one primary (amenorrhea, low bone mineral density, low follicle-stimulating hormone, luteinizing hormone, or estradiol, resting metabolic rate ≤29 kcal/kg fat-free mass, Low Energy Availability in Females Questionnaire score ≥8) and one secondary indicator of LEA (fasting blood glucose <4 mmol/L, free triiodothyronine <3.5 pmol/L, ferritin <25 μg/L, low-density lipoprotein cholesterol >3.0 mmol/L, fasting insulin <20 pmol/L, low insulin-like growth factor-1, systolic blood pressure <90 mmHg, and/or diastolic blood pressure <60 mmHg). At POST, seven out of 13 athletes (54%) presented with at least one primary and one secondary indicator of LEA, three of whom had also presented with indicators of LEA at PRE. Five out of 13 (39%) athletes had previous stress fracture history, though this was not associated with current indicators of LEA (PRE: r = .52, p = .07; POST: r = −.07, p = .82). In conclusion, elite female sprinters may present with signs and symptoms of LEA, even after off-season rest. Medical and coaching staff should be aware of the signs and symptoms of LEA and relative energy deficiency in sport and should include appropriate screening and intervention strategies when working with sprinters.

scholarly journals Male Flat Jockeys Do Not Display Deteriorations in Bone Density or Resting Metabolic Rate in Accordance With Race Riding Experience: Implications for RED-S

2018 ◽  
Vol 28 (4) ◽  
pp. 434-439 ◽  
Author(s):  
George Wilson ◽  
Dan Martin ◽  
James P. Morton ◽  
Graeme L. Close
Keyword(s):  
Lumbar Spine ◽  
Metabolic Rate ◽  
Bone Health ◽  
Resting Metabolic Rate ◽  
Low Energy ◽  
Fat Free Mass ◽  
Published Data ◽  
Energy Availability ◽  
Mineral Density ◽  
Low Energy Availability

Despite consistent reports of poor bone health in male jockeys, it is not yet known if this is a consequence of low energy availability or lack of an osteogenic stimulus. Given the rationale that low energy availability is a contributing factor in low bone health, we tested the hypothesis that both hip and lumbar bone mineral density (BMD) should progressively worsen in accordance with the years of riding. In a cross-sectional design, male apprentice (n = 17) and senior (n = 14) jockeys (matched for body mass and fat-free mass) were assessed for hip and lumbar spine BMD, as well as both measured and predicted resting metabolic rate (RMR). Despite differences (p < .05) in years of race riding (3.4 ± 2 vs. 16.3 ± 6.8), no differences were apparent (p > .05) in hip (−0.9 ± 1.1 vs. −0.8 ± 0.7) and lumbar Z-scores (−1.3 ± 1.4 vs. −1.5 ± 1) or measured RMR (1,459 ± 160 vs. 1,500 ± 165 kcal/day) between apprentices and senior jockeys, respectively. Additionally, years of race riding did not demonstrate any significant correlations (p > .05) with either hip or lumbar spine BMD. Measured RMR was also not different (p > .05) from predicted RMR in either apprentice (1,520 ± 44 kcal/day) or senior jockeys (1,505 ± 70 kcal/day). When considered with previously published data examining underreporting of energy intake and direct assessments of energy expenditure, we suggest that low BMD in jockeys is not due to low energy availability per se but rather the lack of an osteogenic stimulus associated with riding.

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