Athletes make food choices on a daily basis that can affect both health and performance. A well planned nutrition strategy that includes the careful timing and selection of appropriate foods and fluids helps to maximize training adaptations and, thus, should be an integral part of the athlete's training programme. Factors that motivate food selection include taste, convenience, nutrition knowledge and beliefs. Food choice is also influenced by physiological, social, psychological and economic factors and varies both within and between individuals and populations. This review highlights the multidimensional nature of food choice and the depth of previous research investigating eating behaviours. Despite numerous studies with general populations, little exploration has been carried out with athletes, yet the energy demands of sport typically require individuals to make more frequent and/or appropriate food choices. While factors that are important to general populations also apply to athletes, it seems likely, given the competitive demands of sport, that performance would be an important factor influencing food choice. It is unclear if athletes place the same degree of importance on these factors or how food choice is influenced by involvement in sport. There is a clear need for further research exploring the food choice motives of athletes, preferably in conjunction with research investigating dietary intake to establish if intent translates into practice.

This study describes the physical activity across and within the lifetime of current ultra-endurance exercisers. Participants (n = 115, % female = 42, age range 21 to 74 years) completed a modified version of the Lifetime Physical Activity Questionnaire (LPAQ) to assess physical activity over six life periods (5-12, 13-18, 19-30, 31-45, 46-60 and 61-75 years). Participants then were categorised into five groups according to which of these life periods they demonstrated the largest absolute increase in ultra-endurance exercise (UEE included all running and cycling) compared to the previous life period. All groups demonstrated significant increases (p < .005) in UEE between their categorised life period of largest increase in UEE (IUEE) and the previous life period. Within groups, increases in average UEE MET-hours year-1 ranged from 144% to 402%. Lifetime exercise volumes varied considerably within groups (average lifetime MET-hrs year-1 IUEE13

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PurposeThe physiological mechanisms for alterations in oxygen utilization () and the energy cost of running (Cr) during prolonged running are not completely understood, and could be linked with alterations in muscle and cerebral tissue oxygenation.MethodsEight trained ultramarathon runners (three women; mean ± SD; age 37 ± 7 yr; maximum 60 ± 15 mL min−1 kg−1) completed a 6 hr treadmill run (6TR), which consisted of four modules, including periods of moderate (3 min at 10 km h−1, 10-CR) and heavy exercise intensities (6 min at 70% of maximum , HILL), separated by three, 100 min periods of self-paced running (SP). We measured , minute ventilation (), ventilatory efficiency (), respiratory exchange ratio (RER), Cr, muscle and cerebral tissue saturation index (TSI) during the modules, and heart rate (HR) and perceived exertion (RPE) during the modules and SP.ResultsParticipants ran 58.3 ± 10.5 km during 6TR. Speed decreased and HR and RPE increased during SP. Across the modules, HR and increased (10-CR), and RER decreased (10-CR and HILL). There were no significant changes in , , Cr, TSI and RPE across the modules.ConclusionsIn the context of positive pacing (decreasing speed), increased cardiac drift and perceived exertion over the 6TR, we observed increased RER and increased HR at moderate and heavy exercise intensity, increased at moderate intensity, and no effect of exercise duration on ventilatory efficiency, energy cost of running and tissue oxygenation.

Physical exercise requiring oxidative energy transfer increases pulmonary ventilation (V E). In an air polluted environment, the exercise-induced increase in V E increases the volume of toxic gases and number of toxic particles to which the pulmonary system is exposed. Using a respiratory air-filtering device (RAFD) during exercise decreases exposure to inhaled toxic gases and particles. However, a RAFD creates external resistance to inspiration and expiration which could decrease pulmonary muscle function and pulmonary volumes, and creates an external mechanical dead-space which produces fractional rebreathing which could increase pulmonary flowrates. This experiment tested the hypotheses that using a RAFD during exercise would; decrease post-exercise peak inspiratory pressure (P PI) and peak expiratory (P PE) pressure, FVC and FEV 1 , and increase post-exercise flowrates. Using a repeated-measures, counterbalanced design, six healthy moderately aerobically-trained, men (mean ± SD; age 24.7 ± 1.7 years; peak oxygen utilization [VO 2peak ] 42.8 ± 5.3 ml kg-1 min-1) completed two 30 min exercise test sessions at a power output equal to 75% VO 2peak. One session was performed not using (NORAFD), and one using a RAFD (Moldex 8000) fitted with organic vapor cartridges and combined dust and mist pre-filters (inspiratory resistance = 0.216 kPa, expiratory resistance = 0.094 kPa at 85.0 l min-1). All pulmonary function tests were performed immediately pre-(Pre) and 0 (Post-0), 5 (Post-5), and 15 (Post-15) min post-exercise. There was a significant (p<0.05) main effect of time with an increase in FEV 1 , FEV 1 /FVC%, PEF, and FEF 50% from Pre to Post-0. There were no other within or between condition differences in any of the pulmonary muscle pressures, volumes or flowrates. It was concluded that using a RAFD during moderate intensity medium duration exercise does not affect post exercise pulmonary function.