Sports Nutrition: What the Future may Bring

The field of sports nutrition is a dynamic one. Core competencies in exercise physiology, psychology, integrated metabolism and biochemistry are the initial parameters for a successful career in sports nutrition. In addition to the academic fundamentals, it is imperative that the sports nutritionist understand the sport in which our client participates. This sport specific understanding should manifest itself in fuel utilization, mechanics of movement, as well as psychological processes that motivate the participant to perform optimally. Sports nutrition as a field has grown substantially over the past 50 years, from glycogen loading to today's scientifically validated ergogenic aids. The last ten years has seen the largest advancement of sports nutrition, with the following areas driving much of the research: the effects of exercise on protein utilization, meal timing to maximize the anabolic response, the potential for ribose to benefit those engaged in high-energy repetitive sports, and creatine and its uses within athletics and medicine. The future of sports nutrition will dictate that we 1) collectively strive for a higher standard of care and education for counseling athletes and 2) integrate different disciplines. We are in an era of unprecedented growth and the new knowledge is constantly evolving. The International Society of Sports Nutrition (ISSN) will contribute to this exciting field in many ways, and we ask for your contribution by sharing your passion, stories, research, and life experiences with us

Nutrient Administration and Resistance Training

Skeletal muscle tissue is tightly regulated throughout our bodies by balancing its synthesis and breakdown. Many factors are known to exist that cause profound changes on the overall status of skeletal muscle, some of which include exercise, nutrition, hormonal influences and disease. Muscle hypertrophy results when protein synthesis is greater than protein breakdown. Resistance training is a popular form of exercise that has been shown to increase muscular strength and muscular hypertrophy. In general, resistance training causes a stimulation of protein synthesis as well as an increase in protein breakdown, resulting in a negative balance of protein. Providing nutrients, specifically amino acids, helps to stimulate protein synthesis and improve the overall net balance of protein. Strategies to increase the concentration and availability of amino acids after resistance exercise are of great interest and have been shown to effectively increase overall protein synthesis. [1-3] After exercise, providing carbohydrate has been shown to mildly stimulate protein synthesis while addition of free amino acids prior to and after exercise, specifically essential amino acids, causes a rapid pronounced increase in protein synthesis as well as protein balance.[1,3] Evidence exists for a dose-response relationship of infused amino acids while no specific regimen exists for optimal dosing upon ingestion. Ingestion of whole or intact protein sources (e.g., protein powders, meal-replacements) has been shown to cause similar improvements in protein balance after resistance exercise when compared to free amino acid supplements. Future research should seek to determine optimal dosing of ingested intact amino acids in addition to identifying the cellular mechanistic machinery (e.g. transcriptional and translational mechanisms) for causing the increase in protein synthesis

Severity of Depressive Symptoms and Accuracy of Dietary Reporting among Obese Women with Major Depressive Disorder Seeking Weight Loss Treatment

An elevation in symptoms of depression has previously been associated with greater accuracy of reported dietary intake, however this association has not been investigated among individuals with a diagnosis of major depressive disorder. The purpose of this study was to investigate reporting accuracy of dietary intake among a group of women with major depressive disorder in order to determine if reporting accuracy is similarly associated with depressive symptoms among depressed women. Reporting accuracy of dietary intake was calculated based on three 24-hour phone-delivered dietary recalls from the baseline phase of a randomized trial of weight loss treatment for 161 obese women with major depressive disorder. Regression models indicated that higher severity of depressive symptoms was associated with greater reporting accuracy, even when controlling for other factors traditionally associated with reporting accuracy (coefficient  =  0.01 95% CI = 0.01 – 0.02). Seventeen percent of the sample was classified as low energy reporters. Reporting accuracy of dietary intake increases along with depressive symptoms, even among individuals with major depressive disorder. These results suggest that any study investigating associations between diet quality and depression should also include an index of reporting accuracy of dietary intake as accuracy varies with the severity of depressive symptoms

Effects of workplace-based dietary and/or physical activity interventions for weight management targeting healthcare professionals : a systematic review of randomised controlled trials

BACKGROUND: The prevalence of overweight and obesity is high amongst healthcare professionals and there is growing interest in delivering weight loss interventions in the workplace. We conducted a systematic review to (i) examine the effectiveness of workplace-based diet and/or physical activity interventions aimed at healthcare professionals and to (ii) identify and describe key components of effective interventions. Seven electronic databases were systematically searched. RESULTS: Thirteen randomised controlled trials met the inclusion criteria, of which seven had data available for meta-analysis. Where meta-analysis was possible, studies were grouped according to length of follow-up (<12 months and ≥12 months) and behavioural target (diet only, physical activity only or diet and physical activity), with outcome data pooled using a weighted random effects model. Nine studies reported statistically significant (between-group) differences. Four studies reported being informed by a behaviour change theory. Meta-analysis of all trials reporting weight data demonstrated healthcare professionals allocated to dietary and physical activity interventions lost significantly more body weight (-3.95 Kg, [95% CI -4.96 to- 2.95 Kg]) than controls up to 12 months follow up. CONCLUSIONS: Workplace diet and/or physical activity interventions targeting healthcare professionals are limited in number and are heterogeneous. To improve the evidence base, we recommend additional evaluations of theory-based interventions and adequate reporting of intervention content.Peer reviewedFinal Published versio

Weight status misperceptions among UK adults: the use of self-reported vs. measured BMI

BACKGROUND: It has been suggested that a significant proportion of overweight and obese individuals underestimate their weight status and think of themselves as being a healthier weight status than they are. The present study examines the prevalence of weight status misperceptions in a recent sample of UK adults, and tests whether the use of self-reported BMI biases estimation of weight status misperceptions. METHODS: Data came from UK adults who took part in the 2013 Health Survey for England. We examined the proportion of overweight vs. normal weight (categorised using self-reported vs. measured BMI) males and females who perceived their weight as being 'about right', as well as how common this perception was among individuals whose waist circumference (WC) placed them at increased risk of ill health. RESULTS: A large proportion of overweight (according to measured BMI) women (31 %) and men (55 %) perceived their weight as being 'about right' and over half of participants with a WC that placed them at increased risk of future ill health believed their weight was 'about right'. The use of self-reported (vs. measured) BMI resulted in underestimation of the proportion of overweight individuals who identified their weight as 'about right' and overestimation of the number of normal weight individuals believing their weight was 'too heavy'. CONCLUSIONS: A large proportion of UK adults who are overweight misperceive their weight status. The use of self-reported BMI data is likely to produce biased estimates of weight status misperceptions. The use of objectively measured BMI is preferable as it will provide more accurate estimates of weight misperception

Short-term effects of unilateral lesion of the primary motor cortex (M1) on ipsilesional hand dexterity in adult macaque monkeys

Although the arrangement of the corticospinal projection in primates is consistent with a more prominent role of the ipsilateral motor cortex on proximal muscles, rather than on distal muscles involved in manual dexterity, the role played by the primary motor cortex on the control of manual dexterity for the ipsilateral hand remains a matter a debate, either in the normal function or after a lesion. We, therefore, tested the impact of permanent unilateral motor cortex lesion on the manual dexterity of the ipsilateral hand in 11 macaque monkeys, within a time window of 60 days post-lesion. For comparison, unilateral reversible pharmacological inactivation of the motor cortex was produced in an additional monkey. Manual dexterity was assessed quantitatively based on three motor parameters derived from two reach and grasp manual tasks. In contrast to the expected dramatic, complete deficit of manual dexterity of the contralesional hand that persists for several weeks, the impact on the manual dexterity of the ipsilesional hand was generally moderate (but statistically significant) and, when present, lasted less than 20 days. Out of the 11 monkeys, only 3 showed a deficit of the ipsilesional hand for 2 of the 3 motor parameters, and 4 animals had a deficit for only one motor parameter. Four monkeys did not show any deficit. The reversible inactivation experiment yielded results consistent with the permanent lesion data. In conclusion, the primary motor cortex exerts a modest role on ipsilateral manual dexterity, most likely in the form of indirect hand postural control

ISSN exercise & sport nutrition review: research & recommendations

Sports nutrition is a constantly evolving field with hundreds of research papers published annually. For this reason, keeping up to date with the literature is often difficult. This paper is a five year update of the sports nutrition review article published as the lead paper to launch the JISSN in 2004 and presents a well-referenced overview of the current state of the science related to how to optimize training and athletic performance through nutrition. More specifically, this paper provides an overview of: 1.) The definitional category of ergogenic aids and dietary supplements; 2.) How dietary supplements are legally regulated; 3.) How to evaluate the scientific merit of nutritional supplements; 4.) General nutritional strategies to optimize performance and enhance recovery; and, 5.) An overview of our current understanding of the ergogenic value of nutrition and dietary supplementation in regards to weight gain, weight loss, and performance enhancement. Our hope is that ISSN members and individuals interested in sports nutrition find this review useful in their daily practice and consultation with their clients