Nutritional strategies of body weight control€¦ · * average weight loss recommended,1.5 ± 0.7...
Transcript of Nutritional strategies of body weight control€¦ · * average weight loss recommended,1.5 ± 0.7...
Pr. Xavier Bigard Professeur agrégé du Val-de-Grâce Medical Director – Union Cycliste Internationale (UCI) Aigle (CH)
Nutritional strategies of body weight control.
French Society of Sports Medicine
« Making the weight »
The long term control
Rapid weight loss (4-7 days), followed by rapid weight gain (3-36 h).
- alteration of the hydro-mineral balance, - immune changes, - disturbances of the androgenic status, - decrease in glomerular filtration, - impaired muscle performance.
What practices?
Slow weight loss (4 weeks). - decrease in fat mass - stability of muscle mass.
Rapid weight loss. - body weight loss by 10-8% (7,5 to 5,5 kg), - dependent on the type of sport, - rapid weight loss lower in wrestling (4% of body weight).
What changes in body weight are expected? (Matthews et al., 2019)
(Barley et al., 2017)
Rapid weight gain (in few hours) - fluid and electrolytes replacement, - replenish the glycogen stores.
What changes in body weight are expected? (Matthews et al., 2019)
What changes in body weight are expected? (Matthews et al., 2019)
What changes in body weight are expected? (Barley et al., 2019)
What changes in body weight are expected? (Reale et al., 2018)
What changes in body weight are expected? (Reale et al., 2018)
Health effects. (Artioli et al., 2016)
Rapid weight loss is at risk for health. - voluntary dehydration, decrease in plasma volume, * cardiovascular risks, - alteration of the thermoregulatory responses. - exercise in hot climate + dehydration * increased risk of heat illness (including heat stroke).
(Tritto et coll., 2018)
- decreased immunity.
Health effects. (Artioli et al., 2016)
Rapid weight loss is at risk for health. - voluntary dehydration, decrease in plasma volume, * cardiovascular risks, - alteration of the thermoregulatory responses. - exercise in hot climate + dehydration * increased risk of heat illness (including heat stroke). - decreased immunity.
Repeated rapid weight losses are also at risk for health. - alteration of body growth, - risk of overweight and obesity after the sports career.
Coaches, trainers and the practices. (Berkovich et al., 2019)
Practices recommended by coaches and trainers. - panel of 68 coaches, (57 men). - 59% were graduates, 71% with more than 20 years of experience. - the majority (90%) report that they monitor body weight prior to
competition. - weight loss interventions * average duration of the weight loss period, 16.2 ± 8.2 days, * average weight loss recommended,1.5 ± 0.7 kg. - the majority recommends a gradual loss of body weight, - using, * gradual dieting, increased exercise, eating less at each meal (mostly) * laxatives, diuretics, diet pills (almost never).
All of these methods are potentially dangerous, with real health risks, as well as, alterations of
- the nutritional status, - sports performances.
« Making the weight »
The long term control
The concept of Energy Availability,
- EA, energy availability, - adequation between - energy intake (EI), - exercise energy expenditure (EE), - energy needed to support the functions required by the body
to maintain optimal health and performance. - EA = EI – EE (/kg fat free mass)
- EA = 45 kcal/kg FFM/day.
The global context
The concept of Energy Availability,
- low EA values, - if, - EE increases, * increased training volume/intensity - EI decreases, * restrictive diet * disordered eating / eating disorder - impaired physiological functioning induced by low EA, * hormonal changes, * metabolic disorders, * functional consequences.
The global context
Relative Energy Deficiency in Sport (RED-S)
Clinical syndrome originally known as the Female Athlete Triad But,
- clinical syndrome that is more than a triad, - at the origin, alterations of energy intake related to, * occasional restrictions of EI, * true eating disorders (EDs).
- multifactorial origin of EDs, * cultural, familial, individual and genetic factors, etc. * particular role of factors related to the sport, - dieting to enhance performance, - pressure of the environment to lose weight, - body weight cycles, - overreaching, overtraining, - inappropriate coaching behavior.
RED-S in female athletes
Clinical syndrome originally known as the Female Athlete Triad But,
- clinical syndrome that is more than a triad, - at the origin, alterations of energy intake related to, * occasional restrictions of EI, * true eating disorders (EDs).
RED-S in female athletes
- prevalence of EI alterations, * 20% in adult female athletes, * 13% in adolescent female athletes.
Clinical syndrome originally known as the Female Athlete Triad But,
- clinical syndrome that is more than a triad, - at the origin, alterations of energy intake related to, - several hormonal alterations, * oligomenorrhea / amenorrhea, * secondary amenorrhea prevalence - 2-5% in collegiate women. - 65 à 69% in dancers and long-distance runners.
RED-S in female athletes
Clinical syndrome originally known as the Female Athlete Triad But,
- clinical syndrome that is more than a triad, - at the origin, alterations of energy intake related to, - several hormonal alterations, - many other consequences.
RED-S in female athletes
extension of the triad concept.
RED-S in male athletes
RED-S in male athletes
RED-S in male athletes
normal range = 7.7 – 29.4 nM n=172
normal range = 140 - 690 nM n=5279
normal range = 0.01-0.015
Athlete entourage, - healthy eating, - good performance does not always mean that the athlete is
healthy.
Recommendations to prevent RED-S
Healthcare professionals,
Recommendations to prevent RED-S
International and national sport federations,
Recommendations to prevent RED-S