Adherence to exercise prescriptions: effects of prescribing moderate versus higher levels of intensity and frequency.

Sedentary adults (N = 379) were randomly assigned in a 2 x 2 design to walk 30 min per day at a frequency of either 3-4 or 5-7 days per week, at an intensity of either 45%-55% or 65%-75% of maximum heart rate reserve. Analyses of exercise accumulated over 6 months showed greater amounts completed in the higher frequency (p = .0001) and moderate intensity (p = .021) conditions. Analyses of percentage of prescribed exercise completed showed greater adherence in the moderate intensity(p = .02) condition. Prescribing a higher frequency increased the accumulation of exercise without a decline in adherence, whereas prescribing a higher intensity decreased adherence and resulted in the completion of less exercise.     

Specific effects of acute moderate exercise on cognitive control

The main issue of this study was to determine whether cognitive control is affected by acute moderate exercise. Twelve participants [4 females (VO_{2 max} = 42 ml/kg/min) and 8 males (VO_{2 max} = 48 ml/kg/min)] performed a Simon task while cycling at a carefully controlled workload intensity corresponding to their individual ventilatory threshold. The distribution-analytical technique and the delta plot analysis [Ridderinkhof, K. R. (2002). Activation and suppression in conflict tasks: Empirical clarification through distributional analyses. In W. Prinz & B. Hommel (Eds.), Common mechanisms in perception and action. Attention and performance (Vol. 19, pp. 494–519). Oxford: Oxford University Press.] were used to assess the role of selective response inhibition in resolving response conflict. Results showed that cognitive processes appeared to be differently affected by acute moderate exercise. Reaction time results confirmed that performance is better (faster without change in accuracy) when the cognitive task is performed simultaneously with exercise. Between-trial adjustments (post-conflict and post-error) highlighted that cognitive control adjustments are also fully efficient during exercise. However, the effect of congruency (Simon effect) appeared to be more pronounced during exercise compared to rest which suggests that the response inhibition is deteriorated during exercise. The present findings suggest that acute moderate exercise differently affects some specific aspects of cognitive functions.     

Magnitude,timing and duration of mood state and cognitive effects of acute moderate exercise in major depressive disorder

BackgroundAcute exercise generally improves mood state and cognitive functioning in healthy adults. However, the impact of acute exercise on primary symptoms in adults with major depressive disorder (MDD) is poorly understood. The present randomized cross-over study evaluated the magnitude, timing, and duration of the psychological effects of 30 min of moderate-intensity cycling exercise compared to quiet rest in 30 adults (21 female) with MDD.MethodsDepressed mood state (Profile of Mood States Short Form-Depression; POMS-D), state anhedonia (anhedonia Visual Analog Scale [VAS], and Dimensional Anhedonia Rating Scale [DARS]), and cognition (inhibition via Stroop and working memory via the 2-back task) were assessed pre, mid, post, 25-, 50- and 75-min after each session.ResultsGeneralized estimating equations demonstrated significant session by time interactions for POMS-D and VAS indicating small-to-large improvements in mood state and anhedonia up to 75 min post-exercise (p < 0.05; Cohen’s d ranges: POMS [-0.69, -0.95]; DARS, [-0.02, 0.16]; VAS [0.33, 0.83]) with greater immediate effects that lessened somewhat across time. For cognition, Stroop reaction time improved during exercise, but was worse at 25- and 50-min post-exercise compared to quiet rest (p < 0.05); no differences were found for 2-back reaction time.LimitationsThe small sample and continued psychological effects at 75 min indicate a potentially longer-lasting response than was measured herein.ConclusionPerforming short bouts of moderate intensity exercise appears to be effective for management of key symptoms (anhedonia, depressed mood state) in adults with MDD. The time immediately post-exercise may be ideal for performing emotionally challenging tasks and/or tasks where a low symptom severity would be helpful (e.g., psychotherapy).     

The effects of reinforcer pairing and fading on preschoolers' snack selections

The effects of reinforcement pairing and fading on preschoolers' snack selections were evaluated in a multiple baseline design. Baseline preferences for snack options were assessed via repeated paired-item preference assessments. Edible, social, and activity-based reinforcers were then exclusively paired with a less preferred snack option. Once the snack paired with reinforcement was selected most frequently, the three types of reinforcement were systematically faded. Frequent selections of the previously less preferred snack option were produced with paired reinforcement, but were disrupted for all children as the paired reinforcement was reduced to low levels. These data showed that paired reinforcement was initially effective in increasing preference for the originally less preferred snack options, but more permanent changes in the value of the snack options were not achieved. Conditions for producing persistent changes in children's snack choices are discussed.     

Enrichment versus exercise effects on motor impairments following cortical removals in rats

Groups of rats were exposed to an enriched environment, given access to an activity wheel, or individually housed in wire mesh cages, impoverished. Rats were exposed in groups of four to the enriched environment or placed individually in the activity wheel for 2 h per day for 25 days preoperatively. Within each exposure group, rats sustained bilateral removals of sensorimotor cortex, or were sham-operated controls. Animals were trained preoperatively to locomote across a narrow elevated runway. Postoperatively, locomotor testing was initiated 17 days after surgery throughout which time all animals were maintained under impoverished conditions. Locomotor deficits following cortical damage were a function of preoperative exposure: enriched rats were least impaired; impoverished rats were most impaired. Rats allowed running wheel activity initially showed the same marked deficits as impoverished animals but recovered more rapidly. The opportunity for physical exercise afforded wheel animals preoperatively may have enhanced motor capabilities that aided recovery. However, physical activity alone did not yield the same protective effects from initial impairment as enrichment. Greater elaboration of neural structures associated with perceptual-motor enrichment probably accounted for the initial sparing of the enriched group.     

Correlates of mood changes in obese women initiating a moderate exercise and nutrition information program

This 20-wk. study assessed relationships of mean difference scores on measures of self-efficacy and self-concept with scores for overall mood in 44 obese women who initiated a moderate exercise and nutrition information program. Simultaneous entry of changes in Physical Self-concept, Exercise Self-efficacy, and Body Areas Satisfaction scale scores into a multiple regression equation explained a significant 38% of the variance in changes in Total Mood Disturbance (R2 = .38, F3,40 = 8.09, p < .001).     

Executive function during and after acute moderate aerobic exercise in adolescents

ObjectivesIn two experiments, we investigated the effects of acute moderate-intensity exercise on aspects of executive function in adolescents.DesignAn experimental design was used.MethodsFifty-five Japanese adolescents (Experiment 1: N = 28; Experiment 2: N = 27) performed a modified flanker task and a modified n-back task to assess inhibitory control and working memory before, during, and after walking on a treadmill at moderate intensity (Experiment 1: 60% maximal heart rate; Experiment 2: 70% maximal heart rate). In a separate session, the same testing sequence was administered while participants sat in a chair.ResultThe results revealed that reaction time for working memory increased during exercise in both experiments, while response accuracy decreased during exercise only at 70% maximal heart rate. Moderate intensity exercise had no substantial effect on inhibition control. Following cessation of the exercise, no effects were observed for either executive function assessment.ConclusionThese results indicate that moderate intensity exercise selectively affects executive function in adolescents. Further, during physical activity, adolescents maintain inhibitory control, but their working memory declines. Further research is required to reveal the mechanisms underlying this phenomenon and to expand beyond the laboratory setting to the areas of sports and physical activities of daily living.     

The effects of internal versus external information processing on symptom perception in an exercise setting

The purpose of our study was to determine the effects of internal versus external attentional focus on symptom perception and performance in an exercise setting. Fifteen introductory psychology undergraduates ran 1 mile under each of three experimental conditions: "word-cue," in which subjects were required to focus externally by listening for a target word heard repeatedly over headphones; "breathing," in which subjects were directed to attend to their own breathing and heart rate; and a control. Results indicated that participants reported significantly less symptomatology, particularly exercise-relevant symptoms, in the word-cue condition than in the breathing or control conditions. The findings are discussed with reference to previous theory in this area, and methodological differences between this and earlier research are delineated.     

Relationship between changes in acute exercise-induced feeling states,self-motivation,and adults' adherence to moderate aerobic exercise

A 14-wk. field study was conducted to estimate a correlation between feeling-state changes induced by moderate (50 to 74% VO2 max; 20 to 30 min.) bouts of cardiovascular exercise and attendance in a new exercise program. Three groups of men and women (ns=22 to 24) were formed for comparative analysis based upon participants' self-motivation (high, medium, low), as measured by the Self-motivation Inventory. Analysis indicated that for the low self-motivation group, attendance was positively correlated with before-to-after exercise difference scores in the Exercise-induced Feeling Inventory subscales of Positive Engagement (r(s)=.48), Revitalization (r(s)=.47). and Tranquility (r(s)=.41) and negatively correlated with difference scores in the Physical Exhaustion subscale (r(s)=-.62). Conversely, for the high self-motivated group generally weaker correlations in the opposite direction were found for each subscale. No definitive pattern was found for the medium self-motivation group. Multiple regression analyses conducted with scores on each Exercise-induced Feeling Inventory subscale supported the moderating effect of Self-motivation Inventory score on exercise attendance: Multiple R2s =.20 to .27. Although limited amounts of the total variance in exercise attendance was explained, practical implications are drawn for prescribing exercise by feeling states. Limitations and replication of results using different types samples and types of exercise are discussed.     

The effects of physique-salient and physique non-salient exercise videos on women's body image, self-presentational concerns, and exercise motivation

This experiment examined the effects of exposure to physique-salient (PS) and physique non-salient (PNS) exercise videos and the moderating influence of perceived physique discrepancies, on body image, self-presentational concerns, and exercise motivation. Eighty inactive women (M age = 26) exercised to a 30 min instructional exercise video. In the PS condition, the video instructor wore revealing attire that emphasized her thin and toned physique. In the PNS condition, she wore attire that concealed her physique. Participants completed pre- and post-exercise measures of body image, social physique anxiety (SPA) and self-presentational efficacy (SPE) and a post-exercise measure of exercise motivation and perceived discrepancies with the instructor's body. No main or moderated effects emerged for video condition. However, greater perceived negative discrepancies were associated with poorer post-exercise body satisfaction and body evaluations, and higher state SPA. There were no effects on SPE or motivation. Results suggest that exercise videos that elicit perceived negative discrepancies can be detrimental to women's body images.     

Insulin, exercise, and dietary effects upon behavioral thermoregulation in albino rats

The objectives of this exploratory research were to assess the effects of insulin preparations (Humulin-regular and NPH) on operant behavior reinforced by schedules of microwave radiation in a cold environment and to measure changes in this thermoregulatory behavior as a function of exercise and food deprivation. Eight albino rats were conditioned to regulate their thermal environment with 6-sec. exposures of microwave (MW) radiation (SAR = 0.34 Watts/kg/(mW/cm2) under FR-1 and FR-10 schedules. Regular-insulin and NPH-insulin sessions were administered alternately with saline-control sessions for 8-hr. durations. Exercise in an activity wheel and 48 hr. of food deprivation (diet) were additional independent variables used to alter thermoregulation. Three randomized-block analysis of variance designs with repeated measures showed that insulin preparations resulted in a suppression of operant responding for heat, yet food deprivation increased rates of microwave responding. These data are interpreted in terms of functional relationships between ambient temperature changes, core body temperature, blood glucose fluctuations, and operant behavior.     

The time course effect of moderate intensity exercise on response execution and response inhibition

This research aimed to investigate the time course effect of a moderate steady-state exercise session on response execution and response inhibition using a stop-task paradigm. Ten participants performed a stop-signal task whilst cycling at a carefully controlled workload intensity (40% of maximal aerobic power), immediately following exercise and 30 min after exercise cessation. Results showed that moderate exercise enhances a subjects’ ability to execute responses under time pressure (shorter Go reaction time, RT without a change in accuracy) but also enhances a subjects’ ability to withhold ongoing motor responses (shorter stop-signal RT). The present outcomes reveal that the beneficial effect of exercise is neither limited to motor response tasks, nor to cognitive tasks performed during exercise. Beneficial effects of exercise remain present on both response execution and response inhibition performance for up to 52 min after exercise cessation.     

Problem perception,optimism, and related states as a function of time of day (diurnal rhythm) and moderate exercise: Two arousal systems in interaction

Two experiments are described in which perceptions of personal problems, optimism, and associated feelings were studied as a function of time of day and moderate exercise (walking). Over multiweek periods, participants completed self-ratings at fixed times of day representing high and low periods of energetic arousal. While ratings on individual days varied, means across all rating days indicated that problems were perceived as more serious at mid-to late afternoon, a period of low energetic arousal, than they were at late morning and after the walk, periods of high energetic arousal. Separate analyses of rated high energy and low tension states, compared to their opposites, indicated that problems were perceived as least serious in the former states. Ratings of optimism and associated feelings were consistent with the problem ratings. Also discussed are theoretical implications regarding moods as predispositional variables, state-dependent memory, and research involving naturalistic settings and aggregated measurements.     

Acute psychological benefits of aerobic exercise: a field study into the effects of exercise characteristics

Eighty volunteers were tested in their natural exercise environment consisting of a fitness centre they regularly attended. Half of the sample exercised on a stationary bicycle, the other half on a treadmill. All participants filled in the Exercise-Induced Feeling Inventory before and after their 20 min of exercise that was performed at self-selected workload. The results revealed that exercise intensity and the other parallel measures like heart rate, perceived exercise intensity and estimates of burned calories were higher in participants who ran in contrast to those who cycled. There were no differences in self-reports of enjoyment of the exercise sessions and in the psychological improvements from pre- to post-exercise between the groups. It is concluded that significant psychological improvements occur even after a 20-min bout of exercise and these changes are independent of the workload or exercise intensity.     

Antecedent exercise and its effects on self-stimulation

The purpose of this study was to evaluate the effects of physical exercise on the self-stimulatory and on-task behaviors of an 8-year-old with developmental disabilities. For 10 min prior to a structured play session, the subject engaged in roller skating. This antecedent activity resulted in a decrease in the subject's self-stimulatory behavior and a corresponding increase in his on-task performance. Applications to educational programs and suggestions for future research are discussed.     

The effects of low and high intensity exercise on emotions,stress and effort

Objectives: To monitor the effects of exercise intensity on regular exercisers' emotions, stress and effort.Design: A two-period crossover design was used in each of two within-subjects field experiments.Methods: Participants were two different groups of regularly exercising male students. Each group exercised using their usual exercise mode in their usual exercise environment. Group 1 (n=38) ran 5.0 km at low and high intensities, Group 2 (n=36) ran 1.7 km at low and high intensities. The analysis of results also examined differences between fast and slow runners.Results: Doubly multivariate (DM) analysis was used in the statistical analysis which indicated that significant changes occurred in pleasant and unpleasant emotions pre- to post-running 5.0 km and 1.7 km. No significant results between high and low running intensities were obtained for the 5.0 km distance. For exercisers running 1.7 km, significant differences between high and low intensity running were found for bodily stress and effort. Several significant findings for pleasant emotions were also obtained between fast and slow runners pre- to post-exercise.Conclusions: The atheoretical nature of some previous studies was avoided by utilising reversal theory's broad range of pleasant and unpleasant emotions as the basis for measurement and analysis. The results show that, for regular exercisers, exercise can lead to improved positive affect and support findings obtained in other studies.     

The effects of leadership style and exercise program choreography on enjoyment and intentions to exercise

ObjectiveThe purpose of the study was to examine the independent (main) and interactive effects of leadership style and exercise program choreography on the enjoyment and future exercise intentions of novice female exercisers.DesignA randomized 2 (leadership style)×2 (exercise choreography) factorial in which a manipulation of leadership style (instructionally and motivationally enriched vs. bland) was crossed with a manipulation of exercise choreography style consisting of either a restricted or a varied set of exercises.MethodsNovice female exercisers (N=75) completed measures of exercise enjoyment and intentions to engage in future step aerobics classes following a 40-minute introductory session of step aerobics.ResultsSignificant (p<0.05) main effects were detected for leadership style and exercise choreography on enjoyment. Socially enriched leadership and varied choreography were associated with greater enjoyment. There were no main or interaction effects for exercise intention.ConclusionsResults show that social and structural factors impact on positive psychological outcomes in a structured exercise setting. Practitioners are encouraged to use these and previous findings to plan introductory exercise sessions. Future research should look at the impact of leadership style, choreography, and class group dynamics on behavioral manifestations such as adherence.     

Influence of aerobic fitness on ratings of perceived exertion during light to moderate exercise

Based on scores from a maximal exercise test on a bicycle ergometer, 24 college-age women were classified into three aerobic-fitness groups. Each subject then completed two randomly ordered cycle exercise bouts at 1-wk. intervals. The exercise bouts required the subjects to pedal for 24 min. attaining and then maintaining a target heart rate of either 30% or 60% of heart-rate reserve. Ratings of perceived exertion (RPE) were reported at the end of each third minute of the exercise period. Repeated-measures analysis of variance indicated the RPE was significantly related to the exercise workload and duration of exercise. No main effect was found for fitness. Two-way interactions were detected for fitness x duration of exercise and for workload x duration of exercise.