Dietary Intake, Body Composition and Iron Status in Experienced and Elite Climbers

Abstract

Climbing has developed into a popular recreational and elite sport, evidenced by a growing number of licenced competition athletes, and the acceptance into the Olympic calendar for Tokyo 2020. A nutritional assessment, including the evaluation of anthropometric and biochemical data, has not been previously reported in climbing athletes. Therefore, the aim of this study was to assess the dietary intake, body composition, and iron status in experienced climbers, across a range of performance levels. Forty climbers (n = 20 male, n = 20 female; 8.8 ± 6.6 years' experience; BMI 21.6 ± 1.7) aged 18-46 (30.3 ± 6.7 years) participated in the study. Dietary intake was recorded in a 3-days diet diary. Body composition was assessed using a skinfold profile and iron status via blood markers. Mean energy intake was 2154.6 ± 450 kcal•day −1 , with 30% of male climbers and 5% of female climbers failing to meet predicted resting metabolic rate. Furthermore, 77.5% of participants failed to meet a predicted energy requirement to support a "moderate" training programme. There were no significant correlations between daily energy intake and exercise volume. Mean intake of carbohydrate, protein and fat was 3.7 ± 0.9 g•kg −1 •day −1 , 1.6 ± 0.5 g•kg −1 •day −1 , and 1.4 ± 0.4 g•kg −1 •day −1 , respectively, with no significant difference between genders. Approximately 17% of males (n =3) and 45% of females (n = 9) had a sub-optimal iron status. Thirty percent of females met the classification criteria for iron deficiency. Mean serum ferritin was significantly greater in males, compared to females (102.7 ± 54.9 vs. 51.4 ± 24.2 µg•L −1 ; p ≤ 0.01) and significantly lower in vegan/vegetarians vs. omnivores, in female climbers only (33.2 ± 14.8 vs. 57.5 ± 24 µg•L −1 ; p = 0.05). No significant differences were observed between climbing ability groups (intermediate-advanced/elite-higher elite) for body composition, dietary intake, or iron status, for males or females. These findings suggest that experienced climbers are at risk of energy restriction and iron deficiency, therefore, routine assessment of nutritional status is warranted. Future research should consider iron status in relation to energy availability and investigate additional factors which may predispose this population to iron deficiency, as well as the risk of relative energy deficiency in sport (RED-S).

Low energy availability and carbohydrate intake in competitive adolescent climbers

“…All the studies with climbers known to us concluded that EI, when compared to predicted energy expenditure (calculated as a product of basal metabolic rate and physical activity factor), was too low in both adolescent and adult climbers (Kemmler, et al, 2006;Merrells, et al, 2008;Sas-Nowosielski & Wycislik, 2019;Zapf, et al, 2001). The only study that determined EA was conducted with adult climbers and the average EA of the participants was 41.4 ± 9 kcal/kg FFM/ day, with significantly higher EA in females than in males (45.6 ± 7 kcal/kg FFM/day vs. 37.2 ± 9 kcal/ kg FFM/day, respectively) (Gibson-Smith, et al, 2020). Further, 78% of elite adult climbers failed to meet the predicted energy requirement to support a moderate level of physical activity with an average of 12 hours of training/week, while 18% failed to meet the predicted RMR values (Gibson-Smith, et al, 2020).…”

“…The only study that determined EA was conducted with adult climbers and the average EA of the participants was 41.4 ± 9 kcal/kg FFM/ day, with significantly higher EA in females than in males (45.6 ± 7 kcal/kg FFM/day vs. 37.2 ± 9 kcal/ kg FFM/day, respectively) (Gibson-Smith, et al, 2020). Further, 78% of elite adult climbers failed to meet the predicted energy requirement to support a moderate level of physical activity with an average of 12 hours of training/week, while 18% failed to meet the predicted RMR values (Gibson-Smith, et al, 2020). In our study, EI of as many as 26% of adolescent climbers (four males, three females) failed to meet the predicted BMR, despite the high training load.…”

“…Energy requirements in adolescent climbers were assessed only in a single study (Watts & Ostrowski, 2014), and recently a pilot study that monitored macronutrient intake and eating attitudes in recreational and competitive adolescent rock climbers was published . Both studies and others, performed with adult climbers (Gibson-Smith, Storey, & Ranchordas, 2020;Kemmler, et al, 2006;Merrells, Friel, Knaus, & Suh, 2008;Sas-Nowosielski & Wycislik, 2019;Zapf, Fichtl, Wielgoss, & Schmidt, 2001), report suboptimal energy intake (EI). The aforementioned studies, except for the study by Gibson-Smith et al (2020), used energy balance (EB) as the traditional metric for determining the adequacy of EI.…”

“…Both studies and others, performed with adult climbers (Gibson-Smith, Storey, & Ranchordas, 2020;Kemmler, et al, 2006;Merrells, Friel, Knaus, & Suh, 2008;Sas-Nowosielski & Wycislik, 2019;Zapf, Fichtl, Wielgoss, & Schmidt, 2001), report suboptimal energy intake (EI). The aforementioned studies, except for the study by Gibson-Smith et al (2020), used energy balance (EB) as the traditional metric for determining the adequacy of EI. However, the body adapts to chronic low EI by resourcing energy needed for training from other physiological functions, which results in a lower resting metabolic rate (RMR) and makes the athletes only appear in EB, while their physiological systems are not working properly in an effort to adapt to a chronic lack of energy (Loucks, Kiens, & Wright, 2011).…”

Prevalence of amenorrhea in elite female competitive climbers

“…Athletes competing in these types of sports have displayed an increased prevalence of disordered eating and chronically low body weight (Sundgot-Borgen and Garthe, 2011 ). Studies assessing eating behavior or nutrient intake among climbers have found disordered eating (Joubert et al, 2020 ), energy restriction (Zapf et al, 2001 ; Michael et al, 2019 ; Sas-Nowosielski and Wycislik, 2019 ), and iron deficiencies (Gibson-Smith et al, 2020 ). Some research indicates no correlation of low BMI and high climbing performance (Grønhaug, 2019 ), yet anecdotal evidence points to a climbing culture that values thinness and often encourages athletes to minimize weight through restrictive eating habits (Leslie-Wujastyk, 2019 ; Lucas, 2021 ).…”