Effects of different intensities of one-off aerobic exercise on state anxiety of female college students taking exercise of different frequencies

Wenchuan LI; Chunmei LIU

ABSTRACT

BACKGROUND:

There are many studies from both domestic and abroad certifying the conclusion that sport exercise can descend state anxiety even though the study outcome is diversified.

OBJECTIVE:

Analysis of the effects of different exercise intensities on state anxiety and physiologic index of female college students taking different exercise frequencies, in order to take exercise of adequate intensity for descending the state anxiety of female college students.

DESIGN:

Matched observations, selecting female college students as subjects stochastically.

SETTING:

Department of Military Sports, China Metrology College.

PARTICIPANTS:

Totally 60 students from the Management Department and Track and Field Department of Shanghai Physical Culture Institute were selected as the subjects from March 2004 to July 2004. The subjects were categorized into two groups frequent exercise group and infrequent exercise group according to exercise frequency (3 times per week, above 30 minutes each time), and each group consisted of 30 subjects.

METHODS:

All subjects were tested on running stage of Swiss-made Monark power bicycle with the time length 20 minutes, exercise intensity 30%VO2max and 75%VO2max. The exercise intensity of subjects was deter mined by the linear relationship between oxygen uptake and heart rate. The state anxiety of the students was assessed with state-trait anxiety scale which have 40 items in a survey questionnaire of two pages. The state anxiety was mainly evaluated with the state anxiety survey questionnaire of items 1-20 under stress condition, and the human emotional experiences were appraised with the trait anxiety survey questionnaire of items 21-40. Each scale was then rated from 1-4, 1 = almost nothing, 2 = a little, 3 = sometimes, 4= approximately always. The questionnaire were handed out and collected respectively in 3 time intervals (immediate, 5 minutes, 20 minutes), before and after exercise the students' heart rate and blood pres sure were tested with PoLar distance cardiotachometer and HeM-741c oMron electronic blood pressure gauge in the same time intervals before and after exercise. MAIN OUTCOME

MEASURES:

Comparison of the effects of different exercise intensities on the state anxiety of female college students taking exercise of different frequencies. Evaluation on their heart rate and blood pressure.

RESULTS:

Totally 60 survey questionnaires were handed out and 60 col lected with the collection percentage of 100%. ①Variation of state anxiety under different exercise intensity. In infrequent exercise group,as compared with those prior to the test, the state anxiety of subjects in infrequent exercise are descended remarkably (P ＜ 0.01) in 30%VO2max exercise of the 3 time intervals immediate, 5 minutes and 20 minutes, with the descent amplitude 9.286, 24.44%; the state anxiety was descended as well in the 75%VO2max exercise of the 3 time intervals, but without remarkable descent amplitude. In frequent exercise group, the state anxiety was descended remarkably (P ＜ 0.01-0.05) in 75%VO2max exercise of the 3 time intervals with the descent amplitude 5.575, 19.5%; the state anxiety was descended remarkably in 30%VO2max exercise for 20 minutes. ② Assessment on heart rate and blood pressure indexes. In frequent exercise group, heart rate showed temporal elevation immediately after test, and soon resumed to previous level before test;diastolic blood pressure (DBP) remained stable. Systolic blood pressure (SBP) showed temporal elevation immediately after test and SBP showed remarkable descent with the greatest degree in 75%VO2max exercise for 20 minutes. In infrequent exercise group, heart rate and SBP showed descent after elevation. SBP showed descent remarkably in 75% VO2max exercise and 30%VO2max exercise for 20 minutes, and more remarkably in 30%VO2max exercise particularly. DBP showed descent remarkably in aerobic exercise 5 minutes or 20 minutes.

CONCLUSION:

75%VO2max aerobic exercise can descend noticeably the state anxiety of female college students in frequent exercise group , and 30%VO2max can eff