Search Results

You are looking at 1 - 10 of 3,070 items for :

  • All content x
Clear All
Restricted access

James Cameron Morehen, Warren Jeremy Bradley, Jon Clarke, Craig Twist, Catherine Hambly, John Roger Speakman, James Peter Morton, and Graeme Leonard Close

Rugby League is a high-intensity collision sport competed over 80 min. Training loads are monitored to maximize recovery and assist in the design of nutritional strategies although no data are available on the total energy expenditure (TEE) of players. We therefore assessed resting metabolic rate (RMR) and TEE in six Super League players over 2 consecutive weeks in-season including one game per week. Fasted RMR was assessed followed by a baseline urine sample before oral administration of a bolus dose of hydrogen (deuterium 2H) and oxygen (18O) stable isotopes in the form of water (2H2 18O). Every 24 hr thereafter, players provided urine for analysis of TEE via DLW method. Individual training load was quantified using session rating of perceived exertion (sRPE) and data were analyzed using magnitude-based inferences. There were unclear differences in RMR between forwards and backs (7.7 ± 0.5 cf. 8.0 ± 0.3 MJ, respectively). Indirect calorimetry produced RMR values most likely lower than predictive equations (7.9 ± 0.4 cf. 9.2 ± 0.4 MJ, respectively). A most likely increase in TEE from Week 1 to 2 was observed (17.9 ± 2.1 cf. 24.2 ± 3.4 MJ) explained by a most likelyincrease in weekly sRPE (432 ± 19 cf. 555 ± 22 AU), respectively. The difference in TEE between forward and backs was unclear (21.6 ± 4.2 cf. 20.5 ± 4.9 MJ, respectively). We report greater TEE than previously reported in rugby that could be explained by the ability of DLW to account for all match and training-related activities that contributes to TEE.

Restricted access

Oleg Zaslavsky, Yan Su, Eileen Rillamas-Sun, Inthira Roopsawang, and Andrea Z. LaCroix

Fatigue is a commonly experienced symptom among older adults ( Avlund, 2010 ). Conceptually, fatigue is defined as a subjective feeling of lack of energy and weariness, which might interfere with one’s ability to function at normal capacity. The prevalence of fatigue is as high as 75% among

Restricted access

Fleur Pawsey, Jennifer Hoi Ki Wong, Göran Kenttä, and Katharina Näswall

, feelings of stress are the likely outcome. It is important to note that stress is not necessarily harmful, especially when stressful episodes are short lived, and in the coaching context, some coaches have even reported a certain amount of stress as being invigorating, boosting energy and motivation

Restricted access

Daniel Crago, John B. Arnold, and Christopher Bishop

The study of running economy (RE) has become increasingly popular in running research, given the relationship between energy expenditure and distance running performance. 1 – 3 The RE is represented by the energy demand for a given velocity of submaximal running and is determined by measuring

Restricted access

Souzana K. Papadopoulou, Sophia D. Papadopoulou, and George K. Gallos

Adequate nutrition is critically important for the achievement of the adolescent athlete’s optimal performance. The purpose of the present study was to evaluate the adequacy of macro- and micro-nutrients in the adolescent Greek female volleyball players’ diet. The subjects of the study consisted of 16 players who were members of the Junior National Team (NP) and 49 players who participated in the Junior National Championship (CP). Dietary intake was assessed using a 3-day food record. Protein intake (16.0 ± 4.9% of total energy intake) was satisfactory, whereas fat consumption (37.5 ± 11.1%) was above recommended values and at the expense of carbohydrate intake (45.9 ± 12.5%). There were no significant differences between NP and CP concerning the intake of macronutrients, except for the fat intake (when this is expressed in grams per day and grams per kilogram of body weight and the saturated fat intake, which were both higher in NP compared to CP players (p < .05). The mean energy intake was 2013 ± 971 and 1529 ± 675 kcal for NP and CP, respectively (p < .05). NP, in particular, consumed fat and especially saturated fat in order to meet their energy needs. As for micronutrients, the volleyball players fell short of meeting the RDA values for calcium, iron, folk acid, magnesium, zinc, and vitamins A, B1, B2, and B6. There was no difference between NP and CP in micronutrient intake. In conclusion, subjects in the current study lacked proper nutrition in terms of quantity and quality.

Restricted access

Alan J. McCubbin, Gregory R. Cox, and Elizabeth M. Broad

This case study describes the nutrition plans, intakes and experiences of five ultra-marathon runners who completed the Marathon des Sables in 2011 and 2013; age 37 (28–43) y, height 184 (180–190) cm, body mass 77.5 (71–85.5) kg, marathon personal best 3:08 (2:40–3:32). MdS is a 7-day, six-stage ultra-running stage race held in the Sahara Desert (total distance of timed stages 1–5 was 233.2 km in 2011, 223.4 km in 2013). Competitors are required to carry all equipment and food (except water) for the race duration, a minimum of 8,360 kJ/day and total pack weight of 6.5–15 kg. Total food mass carried was 4.2 (3.8–4.7) kg or 0.7 (0.5–1.1) kg/day. Planned energy (13,550 (10,323–18,142) kJ/day), protein (1.3 (0.8–1.8) g/kg/day), and carbohydrate (6.2 (4.3–9.2) g/kg/day) intakes on the fully self-sufficient days were slightly below guideline recommendations, due to the need to balance nutritional needs with food mass to be carried. Energy density was 1,636 (1,475–1,814) kJ/100g. 98.5% of the planned food was consumed. Fluid consumption was ad libitum with no symptoms or medical treatment required for dehydration or hyponatremia. During-stage carbohydrate intake was 42 (20–64) g/hour. Key issues encountered by runners included difficulty consuming foods due to dry mouth, and unpalatability of sweet foods (energy gels, sports drinks) when heated in the sun. Final classification of the runners ranged from 11th to 175th of 970 finishers in 2013, and 132nd of 805 in 2011. The described pattern of intake and macronutrient quantities were positively appraised by the five runners.

Restricted access

Wonseok Jang, Yong Jae Ko, Daniel L. Wann, and Daehwan Kim

when sport spectatorship may positively influence happiness by using energy as a key metaphor. The concept of energy has received considerable attention from psychologists, who often use it as a metaphor to understand psychological well-being, such as feelings of enjoyment ( Ryan & Frederick, 1997

Restricted access

Jean Slawinski, Véronique Billat, Jean-Pierre Koralsztein, and Michel Tavernier

The purpose of this study was to estimate the difference between potential and kinetic mechanical powers in running (Pke, Ppe) calculated from the center of mass and one anatomic point of the body located on the lower part of the runner's back, the “lumbar point.” Six runners undertook a treadmill run at constant velocity and were filmed individually with a video camera (25 Hz). The 3-D motion analysis system, ANIMAN3D, uses a numerical manikin (MAN3D) which compares a voluminal subject (the athlete) directly to the manikin which possesses the same voluminal properties. This analysis system allows the trajectories of the center of mass and the lumbar point to be calculated. Then, from these trajectories, potential and kinetic mechanical powers in running are calculated. The results show that the utilization of the lumbar point rather than the runner's center of mass leads to a significant overestimation of Pke and a significant underestimation of Ppe (both p < 0.05). In spite of these differences, however, both methods of calculating Pke and Ppe are well correlated: respectively, r = 0.92; p ≤ 0.01, and r = 0.68; p ≤ 0.05. Taking into account that the trajectory of an anatomic point is experimentally easier to access than that of the center of mass, such a point could be used to estimate the evolution of kinetic or potential energy variation in different cases. However, when the lumbar point rather than the center of mass is used to estimate the mechanical energy produced in running, Pke could appear to be a discriminating parameter, which it is not.

Restricted access

Billy Sperlich, Karsten Koehler, Hans-Christer Holmberg, Christoph Zinner, and Joachim Mester


The aim of the study was to determine the cardiorespiratory and metabolic characteristics during intense and moderate table tennis (TT) training, as well as during actual match play conditions.


Blood lactate concentration (Lac), heart rate (HR, beats per minute [bpm]), oxygen uptake (VO2), and energy expenditure (EE) in 7 male participants of the German junior national team (age: 14 ± 1 y, weight: 60.5 ± 5.6 kg height; 165 ± 8 cm) were examined during six training sessions (TS) and during an international match. The VO2 was measured continuously with portable gas analyzers. Lac was assessed every 1 to 3 min during short breaks.


Mean (peak) values for Lac, HR, VO2, and EE during the TS were 1.2 ± 0.7 (4.5) mmol·L–1, 135 ± 18 (184) bpm, 23.5 ± 7.3 (43.0) mL·kg–1· min–1, and 6.8 ± 2.0 (11.2) METs, respectively. During match play, mean (peak) values were 1.1 ± 0.2 (1.6) mmol·L–1, 126 ± 22 (189) bpm, 25.6 ± 10.1 (45.9) mL·kg–1·min–1, and 4.8 ± 1.4 (9.6) METs, respectively.


For the frst time, cardiorespiratory and metabolic data in elite junior table tennis have been documented demonstrating low cardiorespiratory and metabolic demands during TT training and match play in internationally competing juniors.

Restricted access

Yongming Li, Margot Niessen, Xiaoping Chen, and Ulrich Hartmann

The knowledge of relative energy contributions (W AER %) is of theoretical and practical interest for a given sport. 1 A description of this knowledge seems to be imperative for most textbooks on exercise physiology and training science. 2 , 3 Regarding women’s Olympic kayaking (200- and 500-m