The impact of XXXX on physiological responses during prolonged exercise.

@entity1372 @entity28
BACKGROUND: Prolonged, moderate-intensity exercise training is routinely prescribed to subjects with @entity28 . In the general population, this type of exercise can lead to fluid and @entity1372 imbalance. However, little is known whether @entity28 alters the risk of fluid and @entity1372 imbalances. OBJECTIVE: This study examined physiological responses, such as core body temperature, fluid and @entity1372 balance, in lean (BMI<25), overweight (25<BMI<30) and @entity28 (BMI>30) subjects during prolonged moderate-intensity exercise. SUBJECTS: A total of 93 volunteers (24-80 years), stratified for BMI, participated in the Nijmegen Marches and walked 30-50 km at a self-selected pace. Heart rate and core body temperature were recorded every 5 km. Subjects reported fluid intake, while urine output was measured and sweat rate was calculated. Baseline and post-exercise plasma @entity1372 levels were determined, and urinary specific gravity levels were assessed before and after exercise. RESULTS: BMI groups did not differ in training status preceding the experiment. Exercise duration (8 h 41    1 h 36 min) and intensity (72    9% HR(max)) were comparable across groups, whereas @entity28 subjects tended to have a higher maximum core body temperature than lean controls (P=0.06). Obese subjects demonstrated a significantly higher fluid intake (P<0.001) and sweat rate (P<0.001), but lower urine output (P<0.05) compared with lean subjects. In addition, higher urine specific gravity levels were observed in @entity28 versus lean subjects after exercise (P<0.05). Furthermore, plasma- @entity1372 concentration did not change in lean subjects after exercise, whereas plasma- @entity1372 levels increased significantly (P<0.001) in overweight and @entity28 subjects. Also, overweight and @entity28 subjects demonstrated a significantly larger decrease in body mass after exercise than lean controls (P<0.05). CONCLUSION: Obese subjects demonstrate a larger deviation in markers of fluid and @entity1372 balance than their lean counterparts during prolonged moderate-intensity exercise. These findings suggest that overweight and @entity28 subjects, especially under strenuous environmental conditions, have an increased risk to develop fluid and @entity1372 imbalances.
