|
COPYRIGHT 2006 University of South Alabama
In this investigation, the focus is upon the effects of an acute bout of aerobic exercise upon positive and negative affect as measured by McAuley and Courneya's (1994) exercise specific Subjective Exercise Experiences Scale (SEES). Other inventories that have been used to study the effects of exercise upon positive and negative affect include: Gauvin and Rejeski's (1993) exercise specific Exercise-Induced Feeling Inventory (EFI), the Profile of Mood States (POMS; McNair, Lorr & Droppleman, 1992), Watson, Clark and Tellegen's (1988) Positive and Negative Affect Schedule (PANAS), and the Revised Multiple Affect Adjective Checklist (MAACL-R; Zuckerman & Lubin, 1985).
Berger and Motl (2000) reviewed 25 investigations in which the Profile of Mood States (POMS) was used to measure changes in mood associated with acute bouts of aerobic exercise and physical activity. The vast majority of results show decreases in tension, depression, anger, and confusion associated with acute bouts of moderate intensity exercise. Moderate intensity exercise may not optimize fitness and sport training benefits, but it has consistently been associated with desirable mood changes (Berger & Owen, 1988; Motl, Berger & Wilson, 1996; Tuson, Sinyor, & Pelletier, 1995). Conversely, high intensity exercise has been linked with either no mood changes or undesirable mood changes (Motl et al., 1996; Steptoe & Cox, 1988). Results obtained when using the POMS are generally consistent with those obtained with other instruments such as the EFI and SEES (Treasure & Newberry, 1998; Szabo, Mesko, Caputo & Gill, 1998).
From this brief review of the literature, it would appear that a moderate bout of exercise is superior to either a high or low bout of aerobic exercise for reducing negative affect and increasing positive affect. However, a closer examination is warranted. In the negative affect literature (state anxiety), the notion that high intensity exercise leads to an increase in state anxiety comes primarily from a study reported by Steptoe and Cox (1988). This research was flawed, however, in that exercise intensity was ascertained and manipulated using absolute as opposed to relative workloads. More recently, Cox, Thomas, Hinton and Donahue (2004) manipulated exercise intensity using relative workloads and observed that a high intensity bout of exercise was more effective than a moderate bout in reducing state anxiety in women. The notion that a moderate bout of aerobic exercise is superior to a more intense bout of exercise, in terms of mood modification, was also questioned by research reported by Blanchard, Rodgers, Wilson and Bell (2004). Blanchard et al. (2004) observed that both moderate and intense bouts of aerobic exercise are equally effective in increasing positive well-being and decreasing psychological distress when total volume of work between exercise conditions is equated. Furthermore, in a longitudinal study involving chronic exercise of older adults it was observed that a decrease in exercise intensity across an eight year period was associated with increased depression (Lampinen, Heikkinen & Ruoppila, 2000). These studies question the conventional wisdom that a moderate bout of aerobic exercise is always superior to a more intense bout of exercise. In the current investigation we manipulated exercise intensity as a percent of measured aerobic capacity, as opposed to either an estimate of aerobic capacity or as perceived exercise intensity.
Another important variable that has been studied in the anxiety literature is the notion of a delayed anxiolytic effect. In a study reported by Cox, Thomas, and Davis (2000) it was observed that a moderate or high intensity bout of aerobic exercise did not result in an immediate reduction in state anxiety, but 30 and 60-min following exercise it did. This delay in a reduction in anxiety following a bout of exercise was also observed by Raglin, Turner, and Eksten (1993), Raglin and Wislon (1996) and Cox et al. (2004). A similar effect has not been observed or studied systematically for positive affect. In the current investigation, positive and negative affect are measured up to 90-min post exercise. Because of the similarity between psychological distress and state anxiety it is logical to expect that a similar delayed reduction in psychological distress might occur following exercise.
Variables that have not been adequately studied, relative to positive and negative mood, include age of exerciser and the influence of iron deficiency in female exercisers. Berger, Owen, Mott and Parks (1998) identified age differences as an important independent variable that should be investigated. In the present investigation we included age in the model because we reasoned that older women might respond differently to exercise in terms of mood response. This reasoning was based upon a meta-analysis reported by Petruzzello, Landers, Hatfield, Kubitz and Salazar (1991). In their meta-analysis they observed that the effect size for individuals between the ages of 31-45 was nearly twice as large as for exercisers 18-30 years of age. Also, Cox et al. (2004) reported an interaction between age and exercise intensity after controlling for iron status.
While direct evidence relating iron status to mood is sparse, the biological consequences of iron deficiency may affect mood changes associated with exercise. Iron deficiency results in decreased performance during aerobic exercise (Haas & Brownlie, 2001; Beard, 2001), and in alterations in neurotransmitter systems (Beard, 2001). Furthermore, iron deficiency, determined by low hematocrit (Hct) and hemoglobin (Hb) and by depleted iron stores, i.e., low serum ferritin (sFer) is common in women of reproductive age (Looker, Dallman, Carrol, Gunter, & Johnson, 1997). In this investigation, these hematological variables were taken into consideration to control for iron status and to assess any impact that iron status may have on psychological mood.
The purpose of the present investigation was to study the effects of an acute bout of aerobic exercise on the positive and negative affect of women of different ages, while controlling for iron status. Manipulated independent variables included intensity of exercise, age of participant, and time of measurement. The dependent variables in this investigation were fatigue, psychological distress, and positive well-being. Research hypotheses included the following:
1. Moderate and high intensity bouts of acute aerobic exercise...
Read the full article for free courtesy of your local library.
|
Bookmark this article
Print this article
Link to this article
Email this article
Digg It!
Add to del.icio.us
RSS
