Eighty-nine high school seniors were administered a questionnaire that gathered information on their exercise habits (ranging from rarely to daily), relationships with parents and peers, depressive tendencies, sports involvement, drug use, and academic performance. Students with a high level of exercise had better relationships with their parents (including greater intimacy and more frequent touching), were less depressed, spent more time involved in sports, used drugs less frequently, and had higher grade point averages than did students with a low level of exercise.
Students who are enrolled in physical education classes are spending more time performing physical activities, and they are engaging in strengthening and stretching activities at increasing rates. However, despite regular exercise by some, participation in daily school physical education has shown a decline, and the percentage of time spent in sedentary activities has not decreased (Francis, 1999).
Lack of exercise among young people has been found to contribute to obesity and health problems. The health benefits of exercise include a reduction in low-density lipoproteins and an increase in high-density lipoproteins, improvement in glucose metabolism, increased strength, and a reduction in sports-related injuries (Sothern, Loftin, Suskind, Udall, & Blecker, 1999). Exercise has also been noted to improve cardiovascular fitness in children (Alpert, Field, Goldstein, & Perry, 1990).
In addition, a moderate-intensity exercise program has been reported to have a beneficial effect on the immune system (Nieman & Pedersen, 1999). Specifically, moderate exercise was found to reduce the number of sick days. Enhancement of immune function may derive from the stress-reducing and stress-hormone-decreasing (i.e., cortisol) benefits of exercise.
Although lower levels of depression and anxiety have been reported for adults who engage in sports (Craft & Landers, 1998; Mutrie & Biddle, :L995), little is known about the effects of moderate exercise on depression and anxiety in adolescents. The effects of exercise on adolescents' interpersonal relationships and academic performance are even less understood. Thus, the present study investigated whether exercise contributes to adolescents' well-being, particularly in terms of more satisfactory relationships and better academic performance.
The participants were 89 suburban high school seniors (52 females and 37 males). On average, they were of middle to upper middle socioeconomic status (M = 3.9 on the Hollingshead Two-Factor Index). Their ethnic distribution was as follows: 76% Caucasian, 11% Hispanic, 5% Asian, 3% African-American and 5% other.
The participants completed a 181-item Likert-type questionnaire on the following behavioral and psychological aspects of adolescent life (Field & Yando, 1991). Exercise was assessed on a 5-point Likert scale: rarely (1), sometimes (2), once a week (3), three or more times a week (4), daily (5). Adolescent depression was measured using the Center for Epidemiological Studies Depression Scale (CES-D; Radloff, 1977). The CES-D has a range of 0-60, with a score greater than 16 indicating depression. The CES-D has been standardized for high school populations (Radloff, 1991) and has adequate test-retest reliability, internal consistency, and concurrent validity (Wells, Klerman, & Deykin, 1987). Quality of relationships with parents/friends (Blyth & Foster-Clark, 1987) was assessed on a 5-point Likert scale, ranging from not at all to very much. For example: "How much does your mother accept you no matter what you do?" Intimacy with parents (frequency of personal conversations, doing fun things together), touch (sh owing physical affection to parents or touching, and receiving physical affection from parents or touching), and family support (closeness to siblings and other relatives) were also assessed. …