PURPOSE: Hemodialysis (HD) is a life-saving treatment for end-stage renal disease (ESRD) patients. However, it removes amino acids (AAs) from the circulation, thereby lowering plasma AA concentrations and stimulating muscle catabolism. To prevent deterioration in the nutritional status of HD patients, protein ingestion and exercise during HD are increasingly implemented in clinical practice. Nevertheless, it is not known whether these interventions modulate the removal of AAs from the circulation. METHODS: Therefore, we recruited ten ESRD patients (age: 65±16 y, BMI: 24.2±4.8 kg•m -2 ) undergoing HD to participate in this double-blind, crossover trial. During four 4-h HD sessions each patient ingested, in a randomized order, 40 g protein (PRO) or a placebo (PLA) both at rest, as well as following 30 min of intradialytic exercise (PRO+EX and PLA+EX, respectively). Blood and spent dialysate samples were collected every 30 min throughout HD to assess AA concentrations and, as such, to quantify plasma AA availability and AA removal. RESULTS: Baseline plasma AA concentrations averaged 2.93±0.40 mmol•L -1 , with no differences between interventions (P=0.66). During PLA and PLA+EX interventions, subsequent plasma AA concentrations decreased over time to 1.84±0.18 and 1.83±0.16 mmol•L -1 , respectively (time effect P<0.001), with no differences between interventions (P=0.94). Plasma AA concentrations increased following protein ingestion up to peak values of 4.40±0.45 and 4.37±0.73 mmol•L -1 during PRO and PRO+EX interventions, respectively (time effect P<0.001), with no differences between interventions (P=0.18). Accordingly, a significant effect of protein ingestion (P<0.001), but no effect of intradialytic exercise (P=0.22) was observed in AA availability during PLA, PLA+EX, PRO, and PRO+EX interventions (incremental AUC: -227±54, -208±68, 49±87, and 70±34 mmol•L -1 •240 min -1 , respectively). AA removal was greater during PRO and PRO+EX interventions (16.6±2.2 and 17.3±2.3 g, respectively) when compared to PLA and PLA+EX interventions (9.8±2.0 and 10.2±1.6 g, respectively; protein effect P<0.001; intradialytic exercise effect P=0.32). CONCLUSIONS: Removal of AAs during HD can be compensated for by protein ingestion and is not compromised by intradialytic exercise in ESRD patients.

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The purpose of this study was to initiate the development of an evidence-based sport classification system for powerchair football, a sport that serves athletes with physical impairments. Sport classification is designed to increase participation by minimizing the impact of impairment on competition outcome, and powerchair football lacks an evidence-based system of classification which is required of Paralympic sports. A number of approaches were used to build the theoretical model of sport performance (Step 2 of the International Paralympic Committee model). Key sport activities were identified through surveys of stakeholders and underlying determinants of those key activities were identified through game and database analyses. Current findings support drive control, ball control, communication, and adjustment to the ball as key activities in powerchair football with joint-specific strength and range of motion, sensory, and neurological variables identified as underlying determinants.

The aim of this study was to identify contextual factors that negatively affect activity and participation among powerchair football (PF) players. Thirty-seven semistructured interviews were conducted with PF players (Mage = 27.9 ± 8.2 years) in France (n = 18) and the United States (n = 19). Participants reported acute back and neck pain as the primary morbidities resulting from PF participation, with sustained atypical posture in the sport chair as the primary cause. Competition-related physical and mental stress were also identified as participation outcomes. Accompanying the many benefits of PF, participants recognized negative impacts of discomfort, physical fatigue, and mental fatigue. Interventions such as seating modifications, thermotherapy to combat pain, napping to combat acute physical stress, and mental preparation to manage state anxiety were all identified as prospective interventions.