Bouts Of Moderate-intensity Physical Activity Research Articles

Using Ecological Momentary Assessments and Fitbit Data to Examine Daily Associations Between Physical Activity, Affect and Alcohol Cravings in Patients with Alcohol Use Disorder.

Preliminary studies show that structured physical activity (PA) interventions can reduce negative affect and alcohol use in patients recovering from alcohol use disorder (AUD). The current study tested whether the association between PA, affect, and alcohol cravings can be observed in patients' natural environments (i.e., without a structured intervention) as well. Twenty-five participants with AUD completed 3weeks of ecological momentary assessment (EMA) monitoring and wore Fitbit devices to measure physical activity directly after discharge from partial hospitalization treatment for AUD. PA was operationalized as total steps and consecutive 10-min bouts of moderate-intensity exercise (100 steps/minute). Only 56% of participants engaged in any bouts of moderate-intensity physical activity throughout the 3-week study period (mode = 1 bout), and participants logged an average of 8183 steps/day (SD = 5560). Daily steps were associated with a higher positive affect and lower alcohol cravings, and with higher positive affect the next day, but the effects were very small. No relationships were observed between PA and affect or alcohol cravings at the hourly level except a random effect signifying that bouts of PA were either positively associated or not associated with negative affect in the next hour for different participants. Overall, results suggest that naturalistic PA may be beneficial for a small subset of patients in recovery from AUD, but the majority did not engage in regular exercise or experience improvements in affect and cravings as a result of PA.

Effects of Frequency and Duration of Interrupting Sitting on Cardiometabolic Risk Markers.

Interrupting prolonged sitting with short multiple bouts of moderate-intensity physical activity (PA) can improve postprandial cardiometabolic risk markers. This study examined the effect of high and low frequency PA bouts (matched for total PA duration and energy expenditure) on postprandial cardiometabolic responses when compared with prolonged sitting. In this three-condition randomised crossover trial, 14 sedentary, inactive females (33.8±13.4 years, BMI 27.1±6.3 kg/m2) completed 3, 7.5 h conditions: 1) prolonged sitting (SIT), 2) high-frequency PA breaks (HIGH-FREQ) consisting of 15 ×2 min bouts of moderate-intensity treadmill PA every 30 min, and 3) low-frequency PA breaks (LOW-FREQ) consisting of 3 ×10 min bouts of moderate-intensity treadmill PA every 180 min. The PA bouts were performed at 65% of peak oxygen uptake. Net incremental area under the curve (iAUC) for each 7.5 h condition was calculated for glucose, insulin and triacylglycerol (TAG) concentrations. Insulin iAUC was significantly (p<0.026) lower during HIGH-FREQ (mean [95%CI]; 82.86 [55.02, 110.70] µU/mL∙7.5 h) than LOW-FREQ (116.61 [88.50, 144.73] µU/mL∙7.5 h) and SIT (119.98 [92.42, 147.53] µU/mL∙7.5 h). Glucose and TAG iAUC did not differ between conditions. Engaging in higher-frequency PA breaks may be effective in attenuating postprandial insulin responses compared with lower-frequency PA breaks and prolonged sitting.

Effect of frequent interruptions of sedentary time on nutrient metabolism in sedentary overweight male and female adults.

This study compared 24-h nutrient oxidation responses between a sedentary condition (SED) and a condition in which short 5-min bouts of moderate-intensity physical activity were performed hourly for nine consecutive hours over 4 days (MICRO). To determine whether any shifts in fuel use were due solely to increases in energy expenditure, we also studied a condition consisting of a single isoenergetic 45-min bout of moderate-intensity exercise (ONE). Twenty sedentary overweight or obese adults (10 men/10 women; 32.4 ± 6.3 yr; BMI, 30.6 ± 2.9 kg/m2) completed all three conditions (MICRO, SED, and ONE) in a randomized order. Each condition consisted of a 3-day free-living run-in followed by a 24-h stay in a whole-room calorimeter to measure total energy expenditure (TEE) and substrate utilization. Dietary fat oxidation was also assessed during the chamber stay by administering a [1-13C] oleic acid tracer at breakfast. Energy intake was matched across conditions. Both MICRO and ONE increased TEE relative to SED, resulting in a negative energy balance. HOMA-IR improved in both activity conditions. MICRO increased 24-h carbohydrate oxidation compared with both ONE and SED ( P < 0.01 for both). ONE was associated with higher 24-h total fat oxidation compared with SED, and higher 24-h dietary fat oxidation compared with both SED and MICRO. Differences in substrate oxidation remained significant after adjusting for energy balance. In overweight and obese men and women, breaking up sitting time increased reliance upon carbohydrate as fuel over 24 h, while a single energy-matched continuous bout of exercise preferentially relies upon fat over 24 h. NEW & NOTEWORTHY Insulin sensitivity, as assessed by HOMA-IR, was improved after 4 days of physical activity, independent of frequency and duration of activity bouts. Temporal patterns of activity across the day differentially affect substrate oxidation. Frequent interruptions of sedentary time with short bouts of walking primarily increase 24-h carbohydrate oxidation, whereas an energy-matched single continuous bout of moderate intensity walking primarily increased 24-h fat oxidation.

Effect of ABO blood group on haemostatic parameters in severe haemophilia A patients performing acute moderate-intensity exercise.

: The primary objective was to assess the effect of ABO blood group on von Willebrand factor (VWF) rise induced by four bouts of moderate-intensity physical activity, on pharmacokinetics of a B-domain-deleted recombinant FVIII (BDD-rFVIII), and haemostatic parameters in severe haemophilia A patients with a null mutation. The secondary objective was to compare the response to exercise according to infused product type in a subgroup of patients who previously participated to the same exercise protocol, while treated with a full length recombinant FVIII (FL-rFVIII). Twenty patients had two visits (rest and exercise). Blood samples were drawn before administration of BDD-rFVIII and at 6 time points, until 24 h postinfusion. FVIII activity increased transiently by 1.1-fold, but only after the first exercise session, as compared to rest. VWF:Ag and platelet count were significantly elevated after each session. Mean FVIII half-life and thromboelastography measurements were unchanged with exercise. However, 14 participants had a slight variation of FVIII half-life with exercise compared to rest (from -3.42 h to +2.51 h). Seven patients demonstrated a longer FVIII half-life (four with O blood group), whereas the remainders had a reduced half-life (three with O blood group). FVIII half-life correlated with baseline VWF:Ag at rest (r = 0.70, P < 0.001) and with exercise (r = 0.67, P < 0.002). Recovery was different between FL-rFVIII and BDD-rFVIII at rest (P = 0.032), but no significant differences were observed between half-life of products at rest and with exercise. ABO blood group and the type of rFVIII administered did not influence the response to exercise.

Effects of one versus two bouts of moderate intensity physical activity on selective attention during a school morning in Dutch primary schoolchildren: A randomized controlled trial.

Evidence suggests that physical activity is positively related to several aspects of cognitive functioning in children, among which is selective attention. To date, no information is available on the optimal frequency of physical activity on cognitive functioning in children. The current study examined the acute effects of one and two bouts of moderate-intensity physical activity on children's selective attention. Randomized controlled trial (ISRCTN97975679). Thirty boys and twenty-six girls, aged 10-13 years, were randomly assigned to three conditions: (A) sitting all morning working on simulated school tasks; (B) one 20-min physical activity bout after 90min; and (C) two 20-min physical activity bouts, i.e. at the start and after 90min. Selective attention was assessed at five time points during the morning (i.e. at baseline and after 20, 110, 130 and 220min), using the 'Sky Search' subtest of the 'Test of Selective Attention in Children'. We used GEE analysis to examine differences in Sky Search scores between the three experimental conditions, adjusting for school, baseline scores, self-reported screen time and time spent in sports. Children who performed two 20-min bouts of moderate-intensity physical activity had significantly better Sky Search scores compared to children who performed one physical activity bout or remained seated the whole morning (B=-0.26; 95% CI=[-0.52; -0.00]). Our findings support the importance of repeated physical activity during the school day for beneficial effects on selective attention in children.

Lifestyle and high density lipoprotein cholesterol in postmenopause

Objectives Menopause is characterized by hormonal and metabolic changes. These are linked to increased risk of cardiovascular disease, for which low blood plasma levels of high density lipoprotein (HDL) cholesterol are an independent risk factor. The present study investigated variables linked with basal plasma HDL cholesterol levels and the effects of aerobic training, on their variations, in 40 postmenopausal women.Methods We assessed body composition, dietary habits and maximal aerobic capacity of participants. Characteristics of daily physical activity and plasma lipoproteins were measured. The women walked on 4 days/week, for 14 weeks, at moderate intensity, and they were grouped according to the resulting tertiles of basal plasma HDL cholesterol levels.Results Logistic regression analysis showed that waist-to-hip ratio and number of daily bouts of moderate-intensity physical activity, held for at least 10 consecutive minutes (B10m/day), are predictive variables of basal plasma HDL cholesterol levels. After the training period, the first and second tertiles increased plasma HDL cholesterol levels, while the third tertile decreased plasma HDL cholesterol levels. The tertiles showed different remodelling of spontaneous physical activity: the third tertile reduced B10m/day, while the others did not.Conclusions This study provides knowledge about the relationships of plasma HDL cholesterol levels with characteristics of physical activity. Furthermore, it shows that physical exercise engagement can result in negative compensation of spontaneous physical activity that could counteract or reduce the positive effects of the aerobic training on plasma HDL cholesterol levels.

Influence of Moderate, Daily Physical Activity On Body Composition and Blood Lipid Profile in Swedish Adults

Health organizations suggest that adults ought to engage in at least 30 minutes of moderate-intensity daily physical activity. This study investigated the effects of a 30-minute single daily bout of brisk walking upon risk factors for coronary heart disease with blood lipid profile in particular. Thirty-three (25-45 y) adults, were randomly assigned into an exercise group (EG; n=16, 9w) and a control group (CG; n=17, 6w). The EG walked briskly 30 minutes daily during the 3-week test period. Compliance/adherence was maximal throughout the 3-week intervention due to stringent daily monitoring. The EG showed a significant decrease in concentrations of low density lipoprotein cholesterol (LDL-C) and total cholesterol (TC) during the intervention period. A significant inverse correlation between Δ energy expenditure/day and ΔLDL-C (r=-0.39, P<.05) and an improvement in weight and BMI in the EG was found. Average steps during 30 minutes brisk walking bout was 3669 steps/bout generating a mean energy expenditure of 191 kcal/ bout. The most unique findings were that daily single bouts of moderate-intensity physical activity for 30 minutes, during 3 weeks, induced favorable effects upon body weight, BMI, and blood concentration of LDL-C and TC in healthy adults.

Domain-Specific Physical Activity and Self-Report Bias Among Low-Income Latinas Living in San Diego County

Evidence suggests that Latina women appear to be less physically active than women of other racial/ethnic groups. This study evaluated how different domains of physical activity (PA) contributed to overall levels of PA among low-income Latinas, the validity of Latinas' self-reported PA, and potential moderators of self-report bias in PA. A community sample of 105 Latinas (mean age = 35.9 ± 9.0 years; mean body mass index = 31.6 ± 7.2) completed the long form Spanish-language version of the International Physical Activity Questionnaire (IPAQ), wore an accelerometer for seven days, and completed self-reported measures of acculturation and socioeconomic status. Ninety-six percent of IPAQ-reported moderate-intensity PA (MPA) was accrued during household activities, with only 4% accrued during leisure time. Seventy-two percent of participants met national recommendations for PA using IPAQ data, but only 20% met recommendations when measured by accelerometer. When bouts of MPA lasting >10 min were included, 0% met recommendations. Age appeared to moderate self-report bias of vigorous PA, and there were nonsignificant trends for acculturation and income to moderate MPA and vigorous-intensity PA, respectively. Data suggest that it is important to measure household activity of Latinas, and that the IPAQ yield overestimates of self-report PA.

Changes in stepping response to lateral perturbations immediately following a single bout of physical activity

Fatiguing exercise can adversely alter postural stability and therefore may contribute to falling. However, older adults rarely perform exercise to fatigue. This study aimed to determine whether undertaking a single bout of moderate-intensity physical activity, similar to that experienced during daily activity or rehabilitation, altered the ability to recover balance with an outward step response to a lateral perturbation. Thirty-four healthy older adults (mean: 76±5 years) and 31 healthy young adults (29±6 years) underwent a 14-minute, self-paced, moderate-intensity physical activity protocol. Before and immediately after the protocol, their responses to lateral waist-pull perturbations were recorded. For participants who used a single outward step response before and after the perturbation, the changes to the timing of the step phases and the hip abductor muscle activity onsets were compared. Young adults responded with an outward step in 55% of trials before and 70% after activity, whereas this frequency was 35% before and 36% after among older adults. When performed, the timing of steps and muscle activity onsets were not adversely altered following the physical activity in either group, apart from a slightly later stance limb gluteus medius onset after activity, found in both groups. Before and after activity, older adults responded with a single outward step to arrest a fall less frequently than young adults. This may place older adults at risk of overbalancing. However, when responding with this strategy, both young and older adults demonstrated few changes immediately following moderate-intensity physical activity compared with before. They appear to be not adversely affected by moderate physical activity.

Dynamic postural stability is not impaired by moderate-intensity physical activity in healthy or balance-impaired older people

Older people are increasingly being encouraged to be more physically active but this may lead to physiological fatigue, tiredness and other effects, which, at high levels, can adversely alter postural stability. However, older adults rarely perform physical activity at high intensities. This study aimed to determine whether a single bout of moderate-intensity physical activity, similar to that experienced during daily living, alters dynamic postural stability, particularly among those at risk of falling. Thirty-one healthy young, 33 healthy older and 21 balance-impaired older, adults performed a rapid, voluntary step-up task before and immediately after a 14min, self-paced, moderate-intensity physical activity protocol. Timing of step components from vertical ground reaction forces, mediolateral displacement of center of pressure, and onset and amplitude of hip abductor muscle activity were recorded during the step task. All groups demonstrated the same changes after the activity, with slightly shorter weight-shift phase duration, smaller displacement of the center of pressure towards the stance leg during weight shifting, and earlier onset of stance leg gluteus medius activity. These changes indicate improved coordination of the step task after activity. Thus this study showed that dynamic postural stability is not adversely affected immediately following moderate-intensity physical activity, even among balance-impaired elderly.

Impact of dieting status and dietary restraint on postexercise energy intake in overweight women.

To investigate the unknown relationship between dieting status and dietary restraint on postexercise energy intake (PE-EI) in overweight sedentary women after a bout of moderate-intensity exercise. Specifically, this was investigated in women who were categorized as dieting with high restraint, nondieting with high restraint, or nondieting with low restraint. This study consisted of two experimental conditions, exercise (E) and nonexercise (NE) in a counterbalanced-crossover design on 2 different days. On the E day, the subjects participated in moderate-intensity exercise, walking on a treadmill for 60 minutes at 60% to 70% of their maximum heart rate. PE-EI at lunch and 12 hours after was compared on the E and an NE day. Dietary restraint was determined using the Three-Factor Eating Questionnaire. Participants (n = 36) were 26 +/- 7 years of age, sedentary, and had a mean body mass index of 27 +/- 3 kg/m(2). There was a significant interaction (F((2,33)) = 3.32, p = 0.049) of dieting/restraint status and condition (E vs. NE day) on 12-hour EI. The mean difference in 12-hour EI between the E and the NE day was significantly higher (p < 0.01) for the dieting with high restraint than for the nondieting with high restraint. The results of this study demonstrate that dieting status, high dietary restraint, and higher levels of disinhibition may influence PE-EI in overweight women after a bout of moderate-intensity physical activity.

N016 Hemodynamic responses from the accumulation of short bouts of moderate-intensity physical activity in hypertensive, post-menopausal women

N016 Hemodynamic responses from the accumulation of short bouts of moderate-intensity physical activity in hypertensive, post-menopausal women