Effects of chronic suboptimal energy intake on constant-load exercise in young women

The physiologic and metabolic effects of chronic consumption of energy below recommended levels on constant-load exercise was studied in women age 19-24 years. Ten controls (average caloric intake ~ 35 kcal/kg body weight) and 10 subjects with suboptimal energy intake (average caloric intake - 25 kcal/kg body weight) were matched for age, exercise caloric expenditure and percentage of HB-predicted RMR. Subjects (n=20) completed a maximal incremental cycle ergometer test and a 30-minute cycle ergometer test at 75 % of peak oxygen consumption. Although both groups presented a significant increase in ventilation (VE) over time of exercise, the rate of change in VE and end-exercise VE value was significantly greater, F (1 J 18) = 5.63, P < .05, for the suboptimal energy intake group than for the controls. Although not statistically significant (p = 0.454), heart rate (HR) tended to be continuously higher for the suboptimal energy intake group than the control group during the constant-load cycle test. Peripheral ratings of perceived exertion (RPE-L) also tended to be higher for the suboptimal energy intake group at the end of constant-load exercise, however, not significantly (p = 0.072). Two subjects in the suboptimal energy intake group failed to complete the 30-minute submaximal constant-load cycle test; one completed 15 minutes and the other 20 minutes. All subjects in the control group completed the entire submaximal constant-load test (30 minutes). These results suggest that women with chronic suboptimal energy intake have increased difficulty tolerating moderate intensity exercise for 30 minutes (an intensity and duration that mimics a typical exercise session).

Name thesis:degree_name

Master of Science

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Human Nutrition, Foods, and Exercise

Department dc:contributor.department

Human Nutrition, Foods, and Exercise

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

1996

Author dc:creator

• Fritsch, LeaAnn Thompson

Chair dc:contributor.committeechair

• Davis, Shala E.

Committee members dc:contributor.committeemember

• Thomas, Elizabeth A.
• Sebolt, Don R.

• resting metabolic rate
• suboptimal energy intake
• constant-load

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Language dc:language.iso

en

Dc Identifier Other

etd-09182008-063227

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/44800