Bout Of Moderate-intensity Exercise Research Articles

Using a novel computer-based approach to assess the acute effects of exercise on appetite-related measures

Measuring food intake using standard buffet meals can be complicated by sensory and external cues which can alter energy intake. The present study was designed to examine the effects of acute exercise on non-metabolic factors related to appetite and food intake using a computer-based assessment. Twenty-seven men and women participated in two sessions in random order: 60-min walking on the treadmill (exercise trial; EX) or seated rest (control trial; CON). Subjective hunger and fullness, food liking, food utility, and ideal portion size were assessed before and immediately after exercise or rest, and hourly for 2 h. The findings showed that an acute bout of moderate intensity exercise had an anorexigenic effect; characterised by diminished hunger (−17.4%, p = 0.004) and lower prospective ideal portion size (−7.7%, p = 0.003) compared to no exercise. This novel, computer-based assessment, is a useful alternative to buffet meals setting and allows for the determination of non-metabolic factors associated with feeding behaviour in relation to exercise.

Acute moderate-intensity cycling exercise is associated with reduced fatigue in persons with multiple sclerosis

Background Fatigue is a prominent, disabling symptom of MS. The prevalence and impact of fatigue highlights the need to identify approaches for its management. Purpose To examine changes in fatigue associated with an acute bout of moderate-intensity exercise in persons with multiple sclerosis (MS). Methods Females ( N = 25) with MS completed an incremental exercise test on a cycle ergometer to measure peak oxygen consumption (VO 2peak) and on a separate day completed the abbreviated Profile of Mood States (POMS) before performing 20 min of cycle ergometry at 60% VO 2peak. Participants again completed the POMS at 5, 20, and 60 min after exercise. Results There were small-to-moderate reductions in fatigue subscale scores on the POMS 20 ( d = .39) and 60 ( d = .45) min after the acute bout of exercise. Conclusion We conclude that moderate-intensity cycling exercise was associated with reductions in fatigue and might represent an appropriate stimulus for the chronic management of fatigue in persons with MS.

Menstrual cycle effects on perceived exertion and pain during exercise among sedentary women.

Increasing cardiovascular fitness through exercise participation among sedentary people is important for decreasing all-cause mortality. From an intervention perspective, identifying modifiable factors that maximize the successful initiation of exercise is of utmost importance. For women, cyclic hormonal variations can influence aspects of health and health behaviors, from smoking cessation efficacy to physiological responses to exercise. The purpose of this study was to examine the influence of menstrual cycle phase and hormonal contraceptive (HC) use on subjective response to an initial bout of moderate intensity exercise among previously sedentary women (n = 117). Women completed a treadmill exercise challenge session at 65% of their previously determined maximum oxygen consumption (Vo(2) max) during the early follicular, late follicular, or luteal phase. Participants reported ratings of perceived exertion and pain using Borg's Rating of Perceived Exertion (RPE) and CR10 scales at 10, 20, and 30 minutes during the exercise session. There was a significant menstrual phase x birth control interaction on change in RPE [F(2, 111) = 3.75, p < 0.05] and change in perceived pain [F(2, 110) = 3.31, p < 0.05]. Women in the early follicular phase who were not using HCs had significantly greater increases in RPE and increases in pain compared with women in the late follicular and luteal phases. Our results indicate that the use of HC and cycle phase influence sedentary women's subjective response to exercise. These results have important implications for the timing of exercise interventions aimed at increasing exercise among sedentary women.

A single versus multiple bouts of moderate-intensity exercise for fat metabolism

This study compared the fat metabolism between 'a single bout of 30-min exercise' and 'three bouts of 10-min exercise' of the same intensity (60% maximal oxygen uptake) and total exercise duration (30 min). Nine healthy men participated in three trials: (1) a single 30-min bout of exercise (Single), (2) three 10-min bouts of exercise, separated by a 10-min rest (Repeated) and (3) rest (Rest). Each exercise was performed with a cycle ergometer at 60% of maximal oxygen uptake, followed by 180-min rest. Blood lactate concentration increased significantly after exercise in the Single and Repeated trials (P < 0.05), but the Single trial showed a significantly higher value during the recovery period (P < 0.05). No significant difference was observed in the responses of plasma glycerol concentration. The Repeated trial produced a smaller increase in the ratings of perceived exertion during the exercise (P < 0.01). During the exercise, no significant difference was observed in respiratory exchange ratio (RER) between the Single and Repeated trials. However, the RER values during the recovery period were significantly lower in the Repeated trial than in the Single and Rest trials (P < 0.05), indicating higher relative contribution of fat oxidation in the Repeated trial (P < 0.05). These results suggest that the repetition of 10-min of moderate exercise can contribute to greater exercise-induced fat oxidation compared with a single 30-min bout of continuous exercise.

Eicosanoid Production following One Bout of Exercise in Middle-Aged African American Pre- and Stage 1 Hypertensives

Endothelial dysfunction and a sedentary lifestyle may be involved in the development of hypertension which is proliferative among middle-aged African Americans (AA). Signaling molecules derived from the oxidation of 20-carbon fatty acid molecules known as eicosanoids influence vascular tone. The relationship between aerobic fitness and eicosanoid formation following exercise in middle-aged African American hypertensives is unknown. Purpose. To determine the relationship between aerobic capacity and eicosanoid formation after a bout of moderate-intensity exercise in middle-aged AA hypertensives. Methods. Ten sedentary hypertensive AA underwent 50 min of aerobic exercise at 65% VO2max. Urine was collected for 24 hr on two occasions, prior to testing and immediately following the bout of exercise. Urinary metabolites of prostacyclin (6-keto PGF1α) and thromboxane (11-dTXB2) were measured during the day and night periods by high-performance liquid chromatography (HPLC). Results. 6-keto PGF1α levels significantly increased (P = .04) following the bout of exercise compared to the control day. There was a significant relationship (r = .49, P < .05) between 6-keto PGF1α levels and VO2max during the exercise day. Conclusion. Based on this preliminary study, there appears to be a relationship between aerobic capacity and exercise-induced 6-keto PGF1α production in middle-aged hypertensive AAs. AAs with lower VO2max had lower 6-keto PGF1α formation.

Extracellular heat shock proteins (eHSP70) in exercise: Possible targets outside the immune system and their role for neurodegenerative disorders treatment

The intracellular heat shock protein 70kDa (iHSP70) is a universal marker of stress protein whose expression is induced by different cell stressors, such as heat, metabolite deprivation, redox imbalances and also during physical exercise. The activation of the iHSP70 is sine qua non for the promotion of tissue repair, since the expression of this chaperone confers cytoprotection and also exerts anti-inflammatory effects. On the other hand, exercise also induces the appearance of HSP70 in the extracellular medium (eHSP70) but, so far, the eHSP70 function has been mainly attributed to the activation of the immune system, seeming to perform an opposite function from the iHSP70. Since a moderate intensity exercise bout induces a general anti-inflammatory response even in the presence of an elevated eHSP70, this protein could carry out other functions rather than immune activation. Because exercise generates heat and metabolic challenges (especially on glucose metabolism) we suggests that the motoneurons, a very active (possibly one of the most stressed cells during exercise) and also very sensitive cells to heat and glucose metabolism imbalances, could be the major sites for the eHSP70 function. Due to the importance of the iHSP70 for repair and stress adaptation, this protein must be present in abundance on the site of stress and, because of its intrinsic inability response to stress [low heat shock factor 1 (HSF-1) activation] and the structure of the motoneurons (very long cells), the iHSP70, produced on the very far nucleus, is not appropriately transported through the axon to the axon terminal, were it is required. Then, during the exercise, the released eHSP70 can be internalized by the motoneurons and act as intracellular chaperons, protecting this cell against oxidative damage, protein denaturation and many others. Since a decreased iHSP70 expression capacity is associated with neurodegeneration diseases (such as Parkinson, polyglutamine, Amyotrophic lateral sclerosis, Alzheimer's, Huntington's and many others), the understanding of the physiological function of the extracellular HSP70 could be helpful on the treatment of neurodegenerative and other neuronal diseases. Besides that, it could explain some of the beneficial effects of the pharmacological HSP70 activators and also the beneficial effects of the exercise among neuronal cells during neurodegenerative-inducing diseases.

Effects of prior exercise on insulin‐mediated and noninsulin‐mediated glucose uptake in horses during a hyperglycaemic clamp

There is limited information about factors regulating glucose utilisation post exercise in horses. To determine the effects of a single bout of moderate intensity exercise on measures of insulin-mediated (IMGU) and noninsulin-mediated (NIMGU) glucose uptake during a hyperglycaemic clamp (HC). Hyperglycaemic clamps were administered in random order to 8 Standardbreds under 4 conditions: 1) rest, insulinopenia (R-L); 2) rest, hyperinsulinaemia (R-H); 3) post exercise (45 min at ∼ 50% VO2peak), insulinopenia (Ex-L) and 4) post exercise, hyperinsulinaemia (Ex-H). In the R-L and Ex-L trials, somatostatin was infused to suppress insulin secretion and induce insulinopenia. After 30 min, a 2 h HC was initiated with plasma glucose concentrations maintained at ∼ 10 mmol/l by variable glucose infusion. In R-H and Ex-H, regular insulin (1.0 mu/kg bwt/min) was also administered to induce physiological hyperinsulinaemia. Serum insulin and C-peptide concentrations were measured in samples obtained at 10 min intervals. Glucose uptake was calculated from mean glucose infusion rate (GIR) during the last 60 min of the HC. In all HCs C-peptide remained below baseline concentrations, evidence of suppression of insulin secretion by somatostatin. Overall, mean ± s.e. insulin concentrations during the final 60 min of the HC in R-L and Ex-L were 5.7 ± 1.1 and 6.9 ± 1.9 mu/l respectively, and corresponding values in R-H and Ex-H were 64.1 ± 11.1 and 61.2 ± 10.9 mu/l. Prior exercise affected IMGU but not NIMGU. Over the final 60 min of the HC, mean GIR was higher (P < 0.001) in Ex-H (5.6 ± 1.1 mg/kg bwt/min) than in R-H (3.3 ± 0.9 mg/kg bwt/min), whereas mean GIR did not differ (P = 0.26) between R-L (1.2 ± 0.3 mg/kg bwt/min) and Ex-L (1.8 ± 0.5 mg/kg bwt/min). A single bout of moderate intensity exercise increased glucose uptake during a hyperglycaemic clamp under hyperinsulinaemic conditions but not under somatostatin-induced insulinopenia.

The Effects of an Acute Bout of Moderate Intensity Exercise on Anger and EEG Responses During Elicitation of Angry Emotions

Exercise enhances moods such as anxiety and depression, but few studies have specifically been designed to investigate whether acute exercise alters feelings of anger. PURPOSE: In this study, state anger was assessed in 16 men high in trait-anger who also viewed anger-inducing scenes before and after 30 minutes of leg-cycling exercise at 65% VO2-peak. METHODS: Brain oscillatory activity, the event-related late-positive potential (LPP), and self-reports of anger intensity were measured during picture viewing. RESULTS: Angry mood was reduced after exercise, but angry emotions and EEG correlates of angry emotions were not altered by exercise. CONCLUSION: The results indicate that acute exercise reduces angry mood and protects against angry mood induction, but does not change affective or EEG responses during elicitation of angry emotions in college-aged men who have high trait-anger. Future studies should explore the mechanisms underlying the effect of exercise on reducing angry mood, consider alternative anger-induction methods that might induce higher levels of anger, and test the effects of chronic exercise training on anger and its expression.

Metabolic And Vascular Responses Acutely Affected By Meal Consumption And Exercise

Lifestyle strongly regulates vascular and metabolic function, with physical activity eliciting acute, short- and long-term effects. We examined risk factor changes after a single exercise session in sedentary people. PURPOSE: To determine how glucose control, arterial elasticity and inflammatory markers respond to a single bout of moderate intensity exercise performed the day before or immediately prior to a standardized mixed meal. METHODS: Participants (5M/6F) were young (26 y±1), normal BMI (22.7 ± 0.3), untrained (VO2peak 25 ± 1 ml/kg/min), but generally healthy. The test meal (670 kcal, 45/40/15% energy as CHO/fat/pro) was consumed on 3 separate mornings. One trial (no-exercise) was after refraining from moderate-to-vigorous activity for ≥3 days. On the other 2 trials, a 45-min exercise bout at 75% HRmax was performed either 17-hr (prior afternoon) or 1-hr (same morning) before the meal. RESULTS: Post-meal energy expenditure increased (24% above baseline at 1-hr) and fuel oxidation shifted toward CHO but there were no differences between trials. Fasting glucose (83±1 mg/dl) and insulin (6.1±0.8 μIU/ml) were similar among trials, but 3-hr post-meal AUC's were reduced by 9 & 19% (p<0.05), respectively, on the acute exercise trial. Small artery elasticity, measured by diastolic pulsewave contour analysis, was reduced 18-20% from 1-3 hours (p < 0.01) after the meal on the no-exercise trial. This post-meal decline was prevented on both exercise trials, demonstrating both acute and residual benefits of exercise. In contrast, large artery elasticity was not significantly affected by the meal or exercise. After prior-day exercise, fasting SBP (110±1 mmHg) and DBP (61±1) were reduced (p < 0.05) by 3 and 2 mmHg, respectively. These effects may be mediated in part by changes in inflammatory markers like ICAM-1 and VCAM-1, which were reduced 5-6% (p<0.03) by prior-day exercise, C-reactive protein (40% lower after acute exercise) and visfatin (7% lower after acute and prior day exercise). Other putative cyto-/adipokines (IL6, HMW adiponectin, e-selectin) were unchanged. CONCLUSION: These results demonstrate that exercise has positive benefits on metabolic and vascular outcomes in untrained young people that begin to accrue after a single moderate exercise session. Supported by NIH Grant P20 DKRR024215

In‐task and post‐task affective response to exercise: Translating exercise intentions into behaviour

To test whether affective response to an acute bout of exercise can predict regular voluntary exercise, and specifically whether a positive affective response helps translate intentions into behaviour. A prospective correlational design. Participants (N=127) recruited from the community reported intentions to engage in voluntary exercise and frequency of participation in voluntary exercise both at baseline and at a 3-month follow-up. Self-reported positive affect, negative affect, tranquillity, and fatigue were assessed during a bout of moderate intensity exercise. Within subject slopes for increases in positive affect and decreases in fatigue during exercise, and increased tranquillity and decreased fatigue post-exercise were associated with more frequent participation in exercise at follow-up. Changes in negative affect did not predict exercise at follow-up; however, this was likely due to floor effects leading to lack of baseline variability in negative affect. Importantly, a positive affective response to exercise moderated the intention-behaviour relationship, such that those who responded to exercise more favourably exhibited stronger relationships between intentions and future exercise behaviour Conclusions: We conclude that exercise-related increases in positive affect and tranquillity and decreases in feelings of fatigue can aid in the successful translation of exercise intentions into behaviour.

Arterial Stiffness and Endothelial Function

Functional assessment of the blood pressure waveform helps us to obtain an estimation of the arterial stiffness or its converse, arterial elasticity.1 Several epidemiological studies have clearly demonstrated that arterial stiffness is a significant predictor of cardiovascular disease incidence in the general population.2 There is clear evidence now that decreased arterial elasticity or increased arterial stiffness in normotensive and prehypertensive subjects induces increased risk for the development of arterial hypertension. In vitro and in vivo experiments have shown that the vascular endothelium plays a crucial role in vascular tone and consequently in arterial stiffness. However, there are no data available regarding the endothelial pathways involved in the adaptation of arterial mechanics during changes in blood flow. The elegant study by Bellien et al3 in this issue of Hypertension studied the endothelial pathways involved in the adaption of arterial mechanics during changes in blood flow. Besides identifying the “endothelial-derived relaxing factor” nitric oxide (NO) as important in this biological process, a unique aspect found in their study was the “endothelial-hyperpolarizing factor” EDHF. Endothelium-dependent relaxation/vasodilation in response to neurohumoral mediators and physical forces, such as the shear stress caused by blood flow, is generally attributed to the release of NO and/or prostacyclin. However, NO and prostacyclin cannot fully explain these endothelium-mediated vasodilator responses. The relaxations observed in the presence of NO synthase and cyclooxygenase inhibitors are often associated with hyperpolarization of the vascular smooth …

Effects of exercise on cravings to smoke: The role of exercise intensity and cortisol

Research consistently demonstrates that a bout of moderate exercise alleviates cravings to smoke among abstaining smokers. The aims of this study were to examine whether doses of exercise (moderate or vigorous) reduced cravings differently, and whether reductions in cravings were associated with changes in cortisol concentration. Using a within-participant, crossover design, 18 participants conducted three 15-min treatment sessions on separate days: passive, walking (45–50% heart rate reserve), and running (80–85% heart rate reserve) conditions. Participants rated cravings at baseline, mid-treatment, and 0, 10, 20, and 30 min after each treatment. Salivary cortisol samples were collected at baseline, immediately after, and 30 min after each condition. Significant group × time interactions were identified, demonstrating significant reductions in craving items after the walking and running conditions compared with the passive control. No significant differences in craving reductions were found between walking and running conditions. Post hoc comparisons found that running condition cravings to smoke scores were reduced for a longer duration post-treatment than post-walking condition scores. The decline in cortisol concentration was attenuated in the running group only. Vigorous exercise has a similar effect to moderate exercise in terms of the magnitude of craving reduction. However, performing bouts of moderate-intensity exercise may be a better recommendation for reducing cravings.

Effect of a 1-hour single bout of moderate-intensity exercise on fat oxidation kinetics

The present study aimed to examine the effects of a prior 1-hour continuous exercise bout (CONT) at an intensity (Fat max) that elicits the maximal fat oxidation (MFO) on the fat oxidation kinetics during a subsequent submaximal incremental test (IncrC). Twenty moderately trained subjects (9 men and 11 women) performed a graded test on a treadmill (Incr), with 3-minute stages and 1-km·h −1 increments. Fat oxidation was measured using indirect calorimetry and plotted as a function of exercise intensity. A mathematical model (SIN) including 3 independent variables ( dilatation, symmetry, and translation) was used to characterize the shape of fat oxidation kinetics and to determine Fat max and MFO. On a second visit, the subjects performed CONT at Fat max followed by IncrC. After CONT performed at 57% ± 3% (means ± SE) maximal oxygen uptake (V̇o 2max), the respiratory exchange ratio during IncrC was lower at every stage compared with Incr ( P < .05). Fat max (56.4% ± 2.3% vs 51.5% ± 2.4% V̇o 2max, P = .013), MFO (0.50 ± 0.03 vs 0.40 ± 0.03 g·min −1, P < .001), and fat oxidation rates from 35% to 70% V̇o 2max ( P < .05) were significantly greater during IncrC compared with Incr. However, dilatation and translation were not significantly different ( P > .05), whereas symmetry tended to be greater in IncrC ( P = .096). This study showed that the prior 1-hour continuous moderate-intensity exercise bout increased Fat max, MFO, and fat oxidation rates over a wide range of intensities during the postexercise incremental test. Moreover, the shape of the postexercise fat oxidation kinetics tended to have a rightward asymmetry.

Effect Of Histamine-Receptor Blockade On Muscle Glucose Uptake During Recovery From Exercise In Humans

Following a bout of moderate-intensity exercise, skeletal muscle blood flow is increased for up to several hours, increasing delivery of glucose to the muscle and possibly augmenting glucose uptake. Administration of histamine-receptor antagonists that selectively block H1- and H2-receptors significantly blunts postexercise hyperemia and subsequently glucose delivery. Thus, we hypothesized that blocking the histamine-receptor mediated blood flow response would significantly reduce glucose uptake in the skeletal muscle. PURPOSE: To determine the effect of histamine-receptor blockade on muscle glucose uptake across the leg during recovery from moderate-intensity dynamic exercise. METHODS: Healthy subjects (n=2) completed a VO2peak test on a cycle ergometer prior to one of two study days: 1-hour exercise session at 60% of VO2peak on either 1) a control day or 2) a blockade day. Radial artery and femoral vein catheters were placed to determine arterial-venous (a-v) differences in blood glucose concentration across the leg. Blood flow to the leg was measured using Doppler ultrasonography on the common femoral artery. Measurements were made every 20 minutes during postexercise recovery for 2 hours with the subject lying supine. RESULTS: During the first hour of postexercise recovery, leg blood flow was significantly reduced in all subjects on the blockade day (Mean±SD: 257 ml/min ±0) compared to the control day (611 ml/min ±142). Leg glucose uptake was also significantly reduced on the blockade day (22 mg/min ±17) compared to the control day (124 mg/min ±10). Glucose extraction appeared to be reduced by the blockade. Beyond the first hour of postexercise recovery, glucose uptake showed no difference between the two study days. CONCLUSION: When postexercise hyperemia in the leg is blunted via administration of H1- and H2-receptor antagonists, glucose uptake across the leg for the first hour following moderate-intensity dynamic exercise is reduced ∼ 80%. Therefore, the normal response of postexercise hyperemia appears to play an important role in augmenting muscle glucose uptake in healthy humans.

PSYCHOBIOLOGICAL PREDICTORS OF EXERCISE BEHAVIOUR IN POSTMENOPAUSAL WOMEN

Weight gain and the associated increased risk of obesity-related diseases are associated with the postmenopausal period. However, moderate intensity exercise may be protective for postmenopausal women through attenuation of weight gain. Despite this evidence, many postmenopausal women do not engage in regular exercise. As exercise has a positive effect on body composition and the subsequent health of postmenopausal females, an understanding of why exercise levels decline in this population is needed. In particular, understanding the difference in exercise behaviour characteristics of exercising and non-exercising postmenopausal women may encourage more non-exercising postmenopausal women to obtain the health benefits of exercise. An understanding of the exercise behaviour characteristics of exercising and non-exercising postmenopausal women may also provide information for future health promotion policy directions for this population and allow for the formulation of guidelines for exercise professionals. It appears that the life event of menopause can become a barrier or an opportunity for postmenopausal women to exercise, depending on their exercise behaviour characteristics. Postmenopausal women (N=101) resident in North Queensland volunteered for this study. A self-report questionnaire was utilised to determine the participants’ recent exercise history. Participants completed two exercise behaviour scales. The Selfefficacy for Exercise Scale is a barrier-specific, thirteen-item instrument listing common reasons for preventing participation in exercise. The Health Belief Model(HBM) scale required participants to indicate how much they agreed or disagreed with various statements relating to their individual health beliefs related to exercise and obesity. Anthropometric assessments ascertained body mass index and waist-to-hip ratio.Resting heart rate and blood pressure were also measured. Participants then performed a six minute graded exercise test (GXT) to determine estimated maximum oxygen uptake (V& O2max). A second visit required participants to perform a twenty minute moderate intensity exercise bout on a cycle ergometer while measures of pre, during and post-exercise affect were obtained using the Subjective Exercise Experience Scale (SEES). Following data collection, participants were categorised as exercisers (n=53) or non-exercisers (n=48) based on whether they had performed a minimum of 150 minutes of accumulated moderate intensity exercise in the past 7 days. Univariate and multivariate statistical tests including discriminant function analysis (DFA) were utilised to determine whether significant between-group differences existed for the physiological and psychological variables. The non-exercisers had obtained a lower level of education (U = 971.5, p = .03),were at a lower stage of exercise change (U = 308.0, p = .00), had higher resting diastolic blood pressure (F1,99=7.57, p=0.01), BMI (F1,99=33.63, p=0.00) and WHR (F1,99=5.83, p=0.02) and lower cardiorespiratory fitness (F1,99=21.57, p=0.00) and exercise self-efficacy (F1,99=39.56, p=0.00) compared to the exercisers. Each of these variables may therefore represent barriers to exercise adoption for this sample of non-exercising postmenopausal women. DFA determined that the postmenopausal women with higher exercise self-efficacy,lower BMI and higher cardiorespiratory fitness were more likely to be exercisers. DFA also found that the barrier to exercise items of perceived lack of time,difficulty getting to an exercise location and the weather provided the greatest discrimination between exercisers and non-exercisers. Further analysis of exercise self-efficacy revealed that participants at different stages of change possessed different levels of exercise self-efficacy. Participants with the lowest exercise self-efficacy were in the precontemplation and contemplation stages of change, while participants with the highest exercise self-efficacy were in the action and maintenance stages. DFA results for the HBM scale revealed that the non-exercising postmenopausal women had higher perceptions of susceptibility to developing an obesity-related disease, perceived a greater number of consequences from participating in regular exercise and felt they were less health motivated to control an obesity-related disease compared to the exercising women. Separate mixed design repeated measures ANOVA found that no significant between-group differences occurred for positive well-being (SEESa) and fatigue(SEESc)during twenty minutes of moderate intensity exercise. However,follow-up univariate contrasts (Bonferroni)found that the acute exercise bout did have a beneficial effect for both groups across time, with higher SEESa scores postexercise compared to pre and during exercise. Additionally, SEESc scores for both groups were lower postexercise compared to during the latter stages of exercise. Further research on postmenopausal women residing in Australian metropolitan cities is recommended for determining whether the differences found in this study are unique to postmenopausal women residing in regional North Queensland.

The short term effects of exercise and omega‐3 fatty acids on the plasma lipid profile in Wheaton College students

Dyslipidemia plays a major role in the development of atherosclerosis, an underlying factor in cardiovascular disease. Both exercise and dietary modifications are key to positively influence lipid profile. The purpose of this study was to examine the immediate effects of a single bout of moderate‐intensity exercise and short‐term consumption of omega‐3 fatty acids on the plasma lipid profile in men and women. Fourteen Wheaton College students (7 males and 7 females) participated in 2 single bouts of 60 minutes, moderate‐intensity exercise (55‐60% of estimated HRmax), separated by a 14 day consumption of 3 g of fish oil per day. Plasma lipid profile was measured before and after each bout of exercise; measurements were grouped as baseline (BA), post‐exercise (PE), post‐fish oil (PF), or post‐exercise and fish oil (PEF). Significant differences were found in female TRIG, male HDL, female VLDL, and male ratio TC/HDL (P &lt; 0.05). From BA to PEF, males had significantly higher HDL values by 16%, and significantly lower TC/HDL values by 13% (p &lt; 0.017). TRIG and VLDL levels in females were significantly increased by 47% and 55% (p &lt; 0.017) from BA to PEF, respectively. Separately, acute exercise and short‐term fish‐oil intake were not shown to significantly change the lipid profile; however, when combined, HDL increased in males, and TC/HDL decreased in males.

Immunological changes after a single bout of moderate-intensity exercise in a hot environment

This study was aimed to evaluate the possible changes caused by a single bout of moderate-intensity exercise in a hot environmental temperature on the immune function and on inflammatory markers. A total of 22 young male adults (VO2(max), 55.4 +/- 3.6 ml x kg(-1) x min(-1)) volunteered to participate in an exercise session of 60 minutes on a treadmill ergometer at moderate speed (60% of the maximum aerobic speed) in hot environmental conditions (35 degrees C and humidity 60%). Total leukocyte numbers, lymphocyte subsets (CD8+, CD4+, CD3+, NK and CD19+), cytokine production capacity by peripheral blood mononuclear cells (PBMCs) (IL-2, IL-4, IL-5, IL-10, IFN-gamma and TNF-alpha) as well as the concentration of several inflammation related proteins (ceruloplasmin, C-reactive protein (CRP), complement factors C3 and C4) were evaluated before and after exercise. The results show that leukocyte and neutrophil absolute values increased (P < 0.001) after the exercise period. In contrast, eosinophil values decreased (P < 0.05) after the exercise. In addition, ceruloplasmin, C3 and C4 values (P < 0.05) increased after exercise. No changes in T lymphocyte subsets, cytokine production, or CRP were observed. These data confirm previous studies suggesting that a 60 min exercise in a hot environment is enough to cause a physiologic adaptation to these special conditions leading to an increase of non-specific immune cells and promoting inflammatory processes. On the other hand, PCR values, lymphocyte subsets and the capacity of cytokine production by PBMC were not changed in a relatively short bout of exercise under these conditions in contrast with previous studies.

Does Exercise Motivation Predict Engagement in Objectively Assessed Bouts of Moderate-Intensity Exercise?: A Self-Determination Theory Perspective

This study examined the utility of motivation as advanced by self-determination theory (Deci & Ryan, 2000) in predicting objectively assessed bouts of moderate intensity exercise behavior. Participants provided data pertaining to their exercise motivation. One week later, participants wore a combined accelerometer and heart rate monitor (Actiheart; Cambridge Neurotechnology Ltd) and 24-hr energy expenditure was estimated for 7 days. After controlling for gender and a combined marker of BMI and waist circumference, results showed autonomous motivation to positively predict moderate-intensity exercise bouts of >or=10 min, or=20 min, and an accumulation needed to meet public health recommendations for moderate intensity activity (i.e., ACSM/AHA guidelines). The present findings add bouts of objectively assessed exercise behavior to the growing body of literature that documents the adaptive consequences of engaging in exercise for autonomous reasons. Implications for practice and future work are discussed.

The impact of dietary restraint and moderate-intensity exercise on post-exercise energy intake in sedentary males

Exercise is often used for successful weight management, particularly by males. However, exercise may have the potential to promote counter-regulatory eating, because of certain cognitive and psychological factors. The purpose of this study was to investigate the unknown role of dietary restraint, BMI, and dieting status on acute and 12-hour post-exercise energy intake (PE-EI) in sedentary males following moderate-intensity exercise. The study consisted of two experimental conditions, exercise and rest, in a counterbalanced-crossover design on two days. Exercise consisted of walking on a treadmill for 60 min. Acute and 12-hour PE-EI were compared on exercise and rest days. Eighty males, mean age 30 ± 8 years, participated in the study and were categorized by dietary restraint level, BMI, and dieting status. The main effects of condition and group, and the interaction were not significant for acute or 12-hour PE-EI, suggesting that a single bout of moderate-intensity exercise did not influence PE-EI in sedentary males in reference to dietary restraint, BMI, and dieting status. Therefore, moderate-intensity exercise as a prescription for weight loss does not appear to promote counter-regulatory eating in sedentary males.

Effect of an Acute After-School Exercise bout on Percent Body Fat using LBIA in Children

PURPOSE: The purpose of this investigation was to examine the effect of an acute after-school exercise bout on percent body fat (%BF) estimated by leg-to-leg bioelectrical impedance analysis (LBIA) in children. METHODS: Thirty-three children (18 girls; 15 boys; mean age 10.3 ± 0.7 years) that were participants in a one-hour after-school exercise program volunteered for this study. Each exercise bout consisted of a proper warm-up/stretching period, followed by the children rotating through a number of circuit based stations and ended with a dynamic, age appropriate group activity. LBIA measured %BF values were obtained immediately before (PRE) and within 5-minutes of completing (POST) the exercise bout. RESULTS: Significant reductions (p < 0.05) in %BF (29.9 ± 11.0 vs. 28.3 ± 11.3 %), impedance (530.7 ± 67.1 vs. 520.4 ± 59.9 Ω) and fat mass (16.4 ± 8.1 vs. 16.0 ± 8.1 kg) were observed POST in the girls when compared to PRE values. For the boys, only body weight was significantly lower (p < 0.05) POST when compared to PRE (48.6 ± 12.0 vs. 48.4 ± 12.1 kg). For the majority of subjects (girls = 93%; boys = 94%), the alteration of %BF POST was less than ± 2.0 % (mean difference = 0.7 %). Mean heart rates during the exercise bout were significantly higher for the girls when compared to boys (160 ± 12 vs. 148 ± 8 beats/min; p < 0.01). CONCLUSIONS: These data indicate that a moderate intensity exercise bout, similar to that performed during a physical education class, will most likely have a limited impact on LBIA %BF estimates when the assessment is performed immediately following exercise. Under certain circumstances (i.e. school physical) this magnitude of change may be considered to have little practical significance; however, when precision is critical, consistency in testing procedures such as conducting LBIA assessments prior to physical activity/exercise is recommended to control for possible exercise-induced alterations in body composition measurements.