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The Impact of Protein Content on Athletes’ Body Composition
Abstract:Several factors contribute to success in sport and diet is one of them. Evidence-based sport nutrition guidelines underline the importance of macro- and micro-nutrients’ balance and timing in order to improve athlete’s physical status and performance. Nevertheless, a high content of proteins is commonly found in resistance training athletes’ diet with carbohydrate intake that is not enough or not well planned. The aim of the study was to evaluate the impact of different protein and carbohydrate diet contents on body composition and sport performance on a group of resistance training athletes. Subjects were divided as study group (n=16) and control group (n=14). For a period of 4 months, both groups were subjected to the same resistance training fitness program with study group following a specific diet and control group following an ab libitum diet. Body compositions were evaluated trough anthropometric measurement (weight, height, body circumferences and skinfolds) and Bioimpedence Analysis. Physical strength and training status of individuals were evaluated through the One Repetition Maximum test (RM1). Protein intake in studied group was found to be lower than in control group. There was a statistically significant increase of body weight, free fat mass and body mass cell of studied group respect to the control group. Fat mass remains almost constant. Statistically significant changes were observed in quadriceps and biceps circumferences, with an increase in studied group. The MR1 test showed improvement in study group’s strength but no changes in control group. Usually people consume hyper-proteic diet to achieve muscle mass development. Through this study, it was possible to show that protein intake fixed at 1,7 g/kg/d can meet the individual's needs. In parallel, the increased intake of carbohydrates, focusing on quality and timing of assumption, has enabled the obtainment of desired results with a training protocol supporting a hypertrophic strategy. Therefore, the key point seems related to the planning of a structured program both from a nutritional and training point of view.
Digital Object Identifier (DOI): doi.org/10.5281/zenodo.3300568Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF
 J. R. Brotherhood, “Nutrition and sports performance”. Sports. Med., vol. 1, n. 5, pp. 350-389, Sep-Oct 1984.
 L. M. Burke and R. Read, “Sport Nutrition. Approaching the nineties”. Sports Med., vol. 8, n. 2, pp. 80-100, Aug 1989.
 K. L. Beck, J. S. Thomson, R. J. Swift and P. von Hurst, “Role of nutrition in performance enhancement and postexercise recovery”. Open Access J Sports Med., vol. 11, n. 6, pp. 259-267, Aug 2015.
 R. B. Kreider et al., “ISSN exercise & sport nutrition review: research & recommendations”. J Int Soc Sports Nutr., vol. 7, n. 7, pp. 1-43, Feb 2010.
 A. E. Jeukendrup, “Periodized Nutrition for Athletes”. Sports Med., vol. 47, n. (Suppl 1), pp. 51-63, Mar 2017.
 J. A. Hawley, E. J. Schabort, T. D. Noakes and S. C. Dennis, “Carbohydrate-loading and exercise performance. An update”. Sports Med., vol. 24, n. 2, pp. 73-81, 1997.
 J. P. Morton, “Increasing lean muscle mass: nutritional and periodization strategies”. BMC Sports Sci Med Rehabil., vol. 7, n. (Suppl 1), p. 9, Aug 2015.
 S. Bilsborough and N. Mann, “A review of issues of dietary protein intake in humans”. Int J Sport Nutr Exerc Metab., vol. 16, n. 2, pp. 129-152, Apr 2006.
 A. Bianco et al., “Protein supplementation and dietary behaviours of resistance trained men and women attending commercial gyms: a comparative study between the city centre and the suburbs of Palermo, Italy”. J Int Soc Sports Nutr., vol. 18, pp. 11-30, Jun 2014.
 J. Antonio, C. A. Peacock, A. Ellerbroek, B. Fromhoff and T. Silver, “The effects of consuming a high protein diet (4.4 g/kg/d) on body composition in resistance-trained individuals”. J Int Soc Sports Nutr., vol. 12, pp. 11-19, May 2014.
 I. Delimaris, “Adverse Effects Associated with Protein Intake above the Recommended Dietary Allowance for Adults”. ISRN Nutr., vol. 18, pp. 126929-126935, Jul 2013.
 S. M. Phillips and L. J. Van Loon, “Dietary protein for athletes: from requirements to optimum adaptation”. J Sports Sci., vol. 29, n. Suppl 1, pp. 29-38, 2011.
 C. P. Lambert, L. L. Frank and W. J. Evans, “Macronutrient considerations for the sport of bodybuilding” Sports Med., vol. 34, n. 5, pp. 317-327, 2004.
 P. A. Tesch, L. L. Ploutz-Snyder, L. Yström, M. J. Castro and G. A. Dudley, “Skeletal Muscle Glycogen Loss Evoked by Resistance Exercise”. J Strength Cond Res., May 1998.
 M. A. Martínez-González et al., “A 14-item Mediterranean diet assessment tool and obesity indexes among high-risk subjects: the PREDIMED trial”. PLoS One, vol. 7, n. 8, p. e43134, 2012.
 National Health and Nutrition Examination Survey (NHANES), Anthropometry Procedures Manual, Centers for Disease Control and Prevention (CDC), 2007.
 A. M. Madden and S. Smith, “Body composition and morphological assessment of nutritional status in adults: a review of anthropometric variables”. J Hum Nutr Diet., vol. 29, n. 1, pp. 7-25, 2016.
 A. S. Jackson and M. L. Pollock, “Generalized equations for predicting body density of men”. Br J Nutr., vol. 40, n. 3, pp. 497-504, 1978.
 H. C. Lukaski, “Methods for the assessment of human body composition: traditional and new”. Am J Clin Nutr., vol. 46, n. 4, pp. 537-56, Oct 1987.
 G. Bonaccorsi et al., “Body composition assessment in a sample of eight-year-old children”. Nutrition, vol. 25, n. 10, pp. 1020-1028, Oct 2009.
 A. Piccoli, B. Rossi, L. Pillon and G. Bucciante, “A new method for monitoring body fluid variation by bioimpedance analysis: the RXc graph”. Kidney Int., vol. 46, n. 2, pp. 534-539, Aug 1994.
 C. E. Gamber et al., “American College of Sports Medicine position stand. Quantity and quality of exercise for developing and maintaining cardiorespiratory, musculoskeletal, and neuromotor fitness in apparently healthy adults: guidance for prescribing exercise”. Med Sci Sports Exerc., vol. 43, n. 7, pp. 1334-1359, Jul 2011.
 Società Italiana di Nutrizione Umana (SINU), Livelli di Assunzione di Riferimento di Nutrienti ed Energia, Società Italiana di Comunicazione Scientifica e Sanitaria S.r.l., 2012.
 B. J. Schoenfeld, A. A. Aragon and J. W. Krieger, “The effect of protein timing on muscle strength and hypertrophy: a meta-analysis”. J Int Soc Sports Nutr., vol. 10, n. 1, p. 53, Dec 2013.
 American College of Sports Medicine (ACSM), “American College of Sports Medicine position stand. Progression models in resistance training for healthy adults”. Med Sci Sports Exerc., vol. 41, n. 3, pp. 687-708, Mar 2009.
 American College of Sports Medicine (ACSM), “Nutrition and Athletic Performance”. Med Sci Sports Exerc., vol. 48, n. 3, pp. 543-568, 2016.
 S. Potgieter, “Sport nutrition: A review of the latest guidelines for exercise and sport nutrition from the American College of Sport Nutrition, the International Olympic Committee and the International Society for Sports Nutrition”. S Afr J Clin Nutr., vol. 26, n. 1, pp. 6-16, Jan 2013.
 B. K. Richard et al., “ISSN exercise & sport nutrition review: research & recommendations”. J Int Soc Sports Nutr., vol. 7, n. 7, pp. 1-43, Feb 2010.
 R. Jäger et al., “International Society of Sports Nutrition Position Stand: protein and exercise”. J Int Soc Sports Nutr., vol. 14, n. 1, pp. 14-20, Jun 2017.
 M. C. Siff and V. Y. Verkhoshansky, “Supertraining: special strength training for sporting excellence: a textbook on the biomechanics and physiology of strength conditioning for all sport”, Denver, 1999.
 J. P. Atherton and J. M. Rennie, “Protein synthesis a low priority for exercising muscle”. J Physiol., vol. 1, n. 573, pp. 288-289, Jun 2006.
 P. J. Atherton and K. Smith, “Muscle protein synthesis in response to nutrition and exercise”. J Physiol., vol. 1, n. 590, pp. 1049-1057, Jan 2012.