Debra J. Crews

A meta-analytic review of aerobic fitness and reactivity to psychosocial stressors

The effects of aerobic fitness on resistance to psychosocial stressors are reviewed. To unravel the inconsistent results in studies examining the relationship between aerobic fitness and psychosocial stress response, a meta-analysis was conducted. The results of 34 studies having 92 effect size estimates from 1,449 subjects were statistically combined to compare psychosocial stressor tasks and arousal measures. The average effect size estimate of 0.48 was significantly different from zero (P less than 0.01), indicating that aerobically fit subjects had a reduced psychosocial stress response compared to either control group or baseline values. The test for the homogeneity assumption showed that it could not be rejected, and thus none of the proposed moderating variables altered the aerobic fitness-psychosocial reactivity relationship. Various underlying mechanisms which may contribute to this response are discussed, and future research directions are presented.

Electroencephalographic measures of attentional patterns prior to the golf putt.

The purpose of this investigation was to determine the attentional focus patterns associated with golf putting performance. Highly skilled golfers (N = 34) were assessed using electroencephalographic (EEG) measures of the motor and temporal cortices during the 3 s prior to the golf putt. Players completed 40, 12-ft putts and performance was measured in cm error from the hole. Three measures of EEG were analyzed: slow shift, 40 Hz, and relative power spectrum; representing readiness to respond, focused arousal, and general cortical activity, respectively. All three EEG measures suggested a decrease in left hemisphere, motor cortex activity as the player prepared to putt. Relative power measures also showed significant increases in right hemisphere activity in both the motor and temporal cortices. During the last second preceding the putt, increased right hemisphere alpha activity correlated with and predicted less error. Hemispheric differentiation was also reduced as subjects prepared to putt and few, but important, differences existed between the motor and temporal cortices. An important distinction occurred in the alpha band. In the motor cortex left hemisphere alpha increased significantly over time while in the temporal cortex, right hemisphere alpha increased as subjects approached stroke initiation. Differences that existed between the attentional patterns from the present study and past sport studies may relate to the use of one versus two hands to initiate the response.

Hemispheric Asymmetry, Cardiac Response, and Performance in Elite Archers

Previous sport research on elite athletes has shown systematic changes in psychophysiological measures, such as heart rate (HR) deceleration and hemispheric asymmetries in EEG activity, in the few seconds prior to executing a motor response. These changes are believed to be due to a more focused attention on the external environment. Using archery (an attentive state), this investigation was designed to examine: (a) whether hemispheric asymmetry and HR deceleration would occur during the aiming period, and (b) if they did, whether this would affect performance. HR and left and right temporal EEG were recorded from 28 right-handed elite archers for 16 shots. The results indicated that (a) there was no HR deceleration; (b) during the aiming period, EEG alpha activity formed the dominant frequency and this was significantly greater in the left than in the right hemisphere; (c) there were no significant right hemisphere EEG changes in spectral power from 3 s before the shot to arrow release, but there were significant left hemisphere increases at 10, 12, and 24 Hz; and (d) at 1 s prior to the shot, there were no significant right hemisphere spectral power differences between best and worst shots, but there were significant left hemisphere differences at 6, 12, and 28 Hz. The relationships among hemispheric asymmetry, HR deceleration, attentional processes, and shooting performance are discussed.

The influence of electrocortical biofeedback on performance in pre-elite archers.

The purpose of the present research was to determine whether EEG biofeedback training could improve archery performance as well as self-reported measures of concentration and self-confidence. Experienced pre-elite male (N = 16) and female (N = 8) archers were randomly assigned to one of three treatment conditions: (a) correct feedback (i.e., greater left hemisphere low frequency activity), (b) incorrect feedback (i.e., greater right hemisphere low frequency activity), and (c) no feedback control. The pretest and posttest consisted of 27 shots, with EEG data collected for the left and right temporal hemispheres (T3, T4). Feedback subjects were then given EEG biofeedback, while control subjects rested for 30 min. Analyses indicated that only the performance measure was significant. The correct feedback group significantly improved performance, while the incorrect feedback group showed a significant performance decrement from pre- to posttest (Ps less than 0.05). The control group showed no significant pre-post differences in performance. EEG analyses showed differences that were consistent with the training given to the incorrect, but not the correct, feedback group. Overall, the results provide some support for the use of known relationships between EEG and performance as an effective means of providing biofeedback to affect the performance of pre-elite archers.

Aerobic Physical Activity Effects on Psychological Well-Being in Low-Income Hispanic Children

Psychological well-being has been generally associated with vigorous aerobic activity and structured aerobic activity in adolescents and children. Low-income children are at greater risk than the general population for experiencing high environmental stress and increased mental health problems. This study investigated the effects of a structured physical fitness program on psychological well-being in low-income Hispanic children. A total of 66, 33 girls, 33 boys, in Grade 4 were randomly assigned to either an Aerobic intensity (n = 34) or a Control intensity physical activity program (n = 32) for 6 wk. Psychological well-being was defined as scores on trait anxiety, depression, and self-esteem, measured, respectively, by the Trait Anxiety Inventory, Beck Depression Inventory, and Rosenberg Self-esteem scale. Analysis showed the children in the Aerobic intensity program significantly (p< .05) improved their cardiovascular fitness as measured by the PWC170 test. After the program was over, the children in this Aerobic group reported significantly (p< .05) less depression. The main effect for self-esteem reflected the Aerobic groups greater self-reported self-esteem. No differences were found on trait anxiety. The effects on depression and self-esteem may only be attributed to the cardiovascular improvement given the higher intensity physical activity program because causation was not assessed here.

Abnormal co-contraction in yips-affected but not unaffected golfers: evidence for focal dystonia.

Up to 30% of golfers develop the yips, an inability to complete a golf stroke, most often affecting short putts, which worsens with anxiety.1,2 Yips may be organic (task-specific dystonia) or psychological (anxiety or “choking”).2–4 We previously found abnormal trains of 4 to 8 Hz, rhythmic, co-contracting bursts of EMG activity in arm muscles of three golfers suggesting a movement disorder. This led to the current investigation. We studied 20 age- and handicap-matched male right-handed golfers, 10 with the yips and 10 without. Handicap is the golfers average score over par over the past ∼10 rounds of golf. Surface EMG electrodes were placed bilaterally on the pectoralis major, deltoid, biceps, triceps, wrist flexors, pronator teres, flexor pollicis longis, wrist extensors, abductor pollicis brevis, and abductor digiti minimi. EEG electrodes were in a standard montage. Recordings were made at a sampling rate of 1,000 Hz, bandpass 1 to 200 Hz using the Neuroscan system (Neuroscan Compumedics, El Paso, TX). Investigators were not …

Effects of Structured Preshot Behaviors on Beginning Golf Performance

Male and female students of beginning golf participated in a “preshot routine” study. 8 men and 7 women learned and practiced a specific routine of actions prior to performing a full swing while 9 men and 6 women (controls) practiced only the swing. Subjective and objective performance measures were completed before and after the 8-wk. training session. Trained men had higher posttraining scores than controls and trained women, but no significant differences were found between trained women and other groups on either measure. As trained men had superior skill before and after training, perhaps a certain level of skill must be established before the preshot routine is effective.

The effects of smokeless tobacco on performance and psychophysiological response

The effects of smokeless tobacco (ST) on psychophysiological response and performance were examined in two studies. Study 1 compared heavy and moderate ST users on psychomotor tasks (simple reaction time/anticipation time and choice reaction time/movement time) in ST (2 g amount) and no smokeless tobacco (NST) conditions. Moderate users performed significantly better than heavy users; there were no significant psychomotor performance differences comparing ST/NST conditions. Heart rate and blood pressure were elevated equally for both groups with the use of ST. Heavy users reported significantly less state anxiety in both ST and NST conditions than moderate users. Study 2 replicated the psychomotor performance results of study 1 when comparing nonusers and ST users who were given four dose amounts of ST (NST, 1/3 mean dose, mean dose, and 5/3 mean) over 4 d. For the math and Stroop tasks, ST use resulted in 12.1% and 10.4% better performance than the NST condition. Physiological measures showed significant elevations during the ST conditions. No differences between dose amounts of ST were apparent for any of the measures. These studies demonstrate that ST users perform better than nonusers when having to react to cognitively challenging task situations.

Psychological state and running economy

The primary purpose of the present review was to critique studies that examined the influence of psychological state (i.e., affect, perception, and cognition) on running economy (RE). However, only six studies included measures of oxygen consumption at a given workload (i.e., economy) and used running as the mode of exercise. Two of the six studies indicated that increased tension was highly correlated (r = 0.81) with increased oxygen cost and that reductions in tension, using stress management techniques, improved RE. Because of the sparsity of studies in this area, a secondary purpose of this review was to examine the influence of psychological state on the physiological and behavioral response to varying modes of exercise. Affect, induced through hypnosis and imagery, was effective in changing the response to exercise (i.e., heart rate, performance). Altered perception through the use of hypnosis or through personality characteristics did not alter the physiological response to exercise, perhaps because of the passive role of the exerciser in these situations. Lastly, cognition (i.e., mental strategy, coping, and biofeedback) elicited changes in the physiological and behavioral responses to exercise. Despite these physiological alterations, there were not changes in oxygen consumption in the majority of the studies. It is possible that changes in selected physiological responses (i.e., respiratory frequency) may be altered (e.g., biofeedback) without changes in oxygen consumption because of accommodation in other areas of the body (i.e., a-VO2 difference). Changes in economy possibly occur when these accommodation effects are overridden by the physiological adaptations resulting from longer training periods. In conclusion, psychological state can influence the physiological and behavioral response to exercise. Furthermore, this review supports the use of a multidisciplinary approach to examine the interactional effects of physiology, biomechanics, psychology, and neurophysiology to adequately determine mechanisms underlying changes in RE.

Attentional Strategy Use by Experienced Distance Runners: Physiological and Psychological Effects

The purpose of this investigation was twofold: (a) to compare most and least economical runners on use of attentional strategies and (b) to determine whether the least economical runners within the subject sample could improve running economy (RE) with the use of an active associative (relaxation) attentional strategy. Subjects (N = 36) completed an initial assessment of attentional style and RE; then the 12 least economical runners ran in each of three laboratory sessions using control, passive associative, and active associative attentional strategies. Results showed that the most economical and least economical runners did not differ in associative style use. The most economical runners, however, reported less dissociation use and more use of relaxation than did the least economical runners. No significant physiological or psychological changes were associated with any of the three attentional strategy conditions. The findings are related to possible differences in how most and least economical runners use associative strategies.