european college of sport science

Thursday, June 25th, 2009
mean head temperature was 1,7 ºC lower in CAP for boys and girls together. Mean heart frequency (HF) during rest periods was lower
than during the exercise bouts, but was not statistically different between CAP and NOCAP. RPE and perception of thermal comfort (PTC)
were not altered due to cap use, but increased during the exercise bouts in CAP and NOCAP. A positive correlation was observed between
Vrun and VO2peak (r=0,64; p=0,002; r2=0,4). Conclusions: Cap use led to a decrease in mean head temperature. However, it
was not sufficient to alter Vrun. Vrun decreases during all exercise bouts may have occurred due the action of a neural mechanism for
homeostasis protection.
LAMBERT, E.V., GIBSON, A St CLAIR and Noakes, T.D. Complex systems model of
fatigue: integrative homoeostatic control of peripheral physiological systems
during exercise in humans. Br J Sports Med 2005; 39: 52-62.
MUNDEL, T.; BUNN S, J.; HOOPER, P.L.; JONES, D.A. The effects of face cooling
during hyperthermic exercise in man: evidence for a integrated thermal,
neuroendocrine and behavioral response. Exp Physiol 2006; 92: 187-195.
15:15 - 16:45
Oral presentations
OP-NU02 Nutrition 2
EFFECTS OF EARLY-EVENING EXERCISE ON ACYLATED GHRELIN, LEPTIN AND PERCEIVED HUNGER MEASURED DURING
A SUBSEQUENT SIMULATED NIGHT-SHIFT
MORRIS, C., FULLICK, F., GREGSON, W., CLARKE, N., DORAN, D., MACLAREN, D., ATKINSON, G.
LIVERPOOL JOHN MOORES UNIVERSITY
Introduction: Shift-work, and particularly night-work, is common in Europe and is an independent risk factor for obesity (Atkinson et al.,
2008). Shift-workers tend to ‘graze’ on high-fat foods during a night-shift and postprandial thermogenesis is lower at night, which, in
combination, may compromise energy balance (Romon et al., 1993). Thus, a reduction in energy intake, by suppressing hunger could
benefit the night-worker. Exercise in the late morning suppresses perceived hunger and associated regulators such as ghrelin (Broom et
al., 2007) and leptin, for many hours. Although it is known that these hormones show circadian variation when measured at rest, no
examination of the responses of these variables to exercise over a subsequent period of night-work has been attempted. We hypothesise
that the responses of perceived hunger, ghrelin and leptin are different when awake and eating at night compared with previous
studies undertaken during the day.
Methods: Six healthy males (age: 30±8 y, body mass: 74.1±6 kg, height: 178±8 cm) completed two trials (exercise and control) in a random
order. In the exercise trial, participants fasted from 10:00 h, consumed a test meal at 18:00 h and then cycled at 50% peak oxygen
uptake between 19:00-20:00 h. Participants then remained awake until 05:00 h, consuming two identical meals at 22:00 and 02:00 h.
Participants rested between 19:00 and 20:00 h in the control trial. During each trial, venous blood samples were drawn at 1-h intervals
between 20:00-05:00 h for the determination of acylated ghrelin, leptin, insulin and glucose concentrations. Perceived hunger was also
recorded at these times. Data were subtracted from baseline and analysed with two factor (trial x time) linear mixed models. Data are
described as mean±SD.
Results: Perceived hunger increased by 0.3±2.0 units throughout the night-work after exercise compared with a reduction of 1.2±2.3 units
in the control trial (P0.05).
Conclusions: We report, for the first time, that evening exercise increases perceived hunger and acylated ghrelin concentration during a
subsequent night-shift. These data are in contrast to those from studies on diurnally-active individuals in which an exercise-mediated
suppression of acylated ghrelin was observed (Broom et al., 2007). Therefore, the effects of exercise on appetite and its regulators appear
different in the nocturnal period, which may help to explain the higher long-term risk of obesity in shift-workers.
References
Atkinson et al., (2008). Sports Med 38:671-85
Broom et al., (2007). J Appl Physiol 102: 2165-2171
Romon et al., (1993). Am J Clin Nutr 57: 467-480
SHORT-TERM MEMORY IN POSTMENOPAUSE. WEIGHT OF DIFFERENT PREDICTORS VARIABLES
DI BLASIO, A., DI DONATO, F., DI RENZO, D., GALLINA, S., NAPOLITANO, G., VALENTINI, P., RIPARI, P.
G. D'ANNUNZIO UNIVERSITY, CHIETI
Introduction: Literature widely shows the memory decline age-related, even if, on the other side, it documented the protective role of
physical exercise, diet, and both hormonal and anthropometric pattern on memory. Aerobic fitness protects and enhances memory
through hippocampal neurogenesis related to the increase of cerebral blood flow exercise-dependent. The dietary habitudes play a
fundamental on the memory functions through its quantitative and qualitative characteristics that can lead to diabetes, hypertension,
stroke and excessive oxidative stress altering brain structure and functions. Both estrogens and leptin patterns have positive functional
implications in memory processes, as excessive stress hormones have a negative role. So that, menopause-related hormonal modifications
becomes important in memory decline. Because the aromatasic activity of adipose tissue may partially replace estrogens deficit
after menopause, in this period, body fat (FM%) has been shown positively related to memory. The aim of this study was to investigate the
influence of dietary, anthropometric, and physiological parameters on short-term memory (STM) in postmenopause.
Methods
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