COMPARATIVE STUDY
JOURNAL ARTICLE

Exercise tolerance and thermoregulatory responses during cycling in boys and men

Thomas Rowland, Sean Hagenbuch, David Pober, Anne Garrison
Medicine and Science in Sports and Exercise 2008, 40 (2): 282-7
18202574

PURPOSE: Physiological responses to exercise in the heat differ between prepubertal children and young adults. Whether these maturity-related variations imply lower exercise tolerance, inferior thermoregulation, and greater risk for heat injury in the child is uncertain. This study directly compared thermoregulatory and cardiovascular responses as well as endurance performance between prepubertal boys and adult males during steady-load cycling in moderately hot and cool ambient conditions with moderate humidity.

METHODS: Eight prepubertal boys (age 11.7 +/- 0.4 yr) and eight adult men (age 31.8 +/- 2.0 yr) performed steady-load cycling to exhaustion at an intensity equivalent to approximately 65% peak V O2 in both hot (approximately 31 degrees C) and cool (approximately 19 degrees C) environments, with fluid intake ad libitum.

RESULTS: Exercise duration in the heat was shorter for both groups (hot: men 30.46 +/- 8.84 min, boys 29.30 +/- 6.19 min; cold: men 42.88 +/- 11.79 min, boys 41.38 +/- 6.30 min), with no significant difference between men and boys (P > 0.05). Increases in rectal temperature, heart rate, and cardiac index were similar between groups and conditions. Stroke index, mean arterial pressure, and arterial venous oxygen difference were stable and similar in both conditions, without group differences. No significant dehydration was observed in men or boys.

CONCLUSIONS: This study failed to reveal differences in exercise tolerance, thermoregulatory adaptation, or cardiovascular response to exercise in the heat between euhydrated prepubertal boys and adult men.

Full Text Links

Find Full Text Links for this Article

Discussion

You are not logged in. Sign Up or Log In to join the discussion.

Trending Papers

Remove bar
Read by QxMD icon Read
18202574
×

Save your favorite articles in one place with a free QxMD account.

×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"