Task switching in overweight children: effects of acute exercise and age

The short-term after effects of a bout of moderate aerobic exercise were hypothesized to facilitate children's executive functioning as measured by a visual task-switching test. Sixty-nine children (mean age=9.2 years) who were overweight and inactive performed a category-decision task before and immediately following a 23-min bout of treadmill walking and, on another session, before and following a nonexercise period. The acute bout of physical activity did not influence the children's global switch cost scores or error rates. Age-related differences in global switch cost scores, but not error scores, were obtained. These results, in concert with several studies conducted with adults, fail to confirm that single bouts of moderately intense physical activity influence mental processes involved in task switching.     

Effects of acute exercise on executive processing, short-term and long-term memory

In the present study, we evaluated the effects of a brief bout of exercise on executive function, short-term memory, and long-term memory tests. Eighteen young adults (mean age 22.2 years, s = 1.6) performed a set-switching test, a Brown-Peterson test, and a free-recall memory test before and after 40 min of moderate aerobic exercise on a cycle ergometer, and two control conditions. Exercise did not facilitate set switching or short-term memory, which suggests that exercise-induced arousal does not influence executive function processes involved in the reconfiguration of information in working memory. Exercise did alter specific aspects of delayed long-term memory. Free recall of items in the primacy and recency portions of the word list declined following the rest and non-exercise conditions, but was maintained after exercise, which suggests that exercise-induced arousal may facilitate the consolidation of information into long-term memory.     

Errata

Abstract

In the present study, we evaluated the effects of a brief bout of exercise on executive function, short-term memory, and long-term memory tests. Eighteen young adults (mean age 22.2 years, s = 1.6) performed a set-switching test, a Brown-Peterson test, and a free-recall memory test before and after 40 min of moderate aerobic exercise on a cycle ergometer, and two control conditions. Exercise did not facilitate set switching or short-term memory, which suggests that exercise-induced arousal does not influence executive function processes involved in the reconfiguration of information in working memory. Exercise did alter specific aspects of delayed long-term memory. Free recall of items in the primacy and recency portions of the word list declined following the rest and non-exercise conditions, but was maintained after exercise, which suggests that exercise-induced arousal may facilitate the consolidation of information into long-term memory.     

Acute effects of exercise and active video games on adults’ reaction time and perceived exertion

The purpose of the present study was to examine the acute effects of resting, aerobic exercise practised alone, and aerobic exercise with active video games (AVG), on complex reaction time (CRT) and the post-exercise acute rate of perceived exertion (RPE) in young healthy adults. The experimental group was composed of 92 healthy young adults, 78 males and 13 females (age M?=?21.9?±?2.7 years) who completed two sessions, A and B. In session A, participants rode 30?min on an ergometer, while in session B they exercised for 30?min on an ergometer while playing an AVG on a Wii. The control group was composed of 30 young adults, 26 males and 4 females (age M?=?21.4?±?2.9 years) who rested for 30?min. In each session, a CRT task was performed before and after exercising or resting, and post-exercise global RPE was noted. Repeated measures general linear model (GLM) and Wilcoxon tests were performed. (1) Both aerobic exercise alone and aerobic exercise combined with AVG improved CRT, while resting did not; (2) aerobic exercise combined with AVG did not improve CRT more than aerobic exercise only; and (3) RPE was lower after aerobic exercise combined with AVG compared with aerobic exercise only. In young adults, exercise produces acute benefits on CRT, and practising exercise with AVG helps to decrease RPE.     

Impact of aerobic exercise trials with varied intensity patterns on perceptions of effort: an evaluation of predicted, in-task, and session exertion

Perceptions of effort provide a sense of momentary exertion during exercise, but may have value when considered prior to and after exercise. The purpose of the present study was to determine the relationship between perceived exertion assessed before, during, and after trials of aerobic exercise fixed for total work but varied on intensity patterns. Twenty participants completed five trials of treadmill exercise that included planned intensity variations every 10 minutes to result in the same total work. Perceived exertion was taken before, during, and after exercise. Analyses confirmed each trial was similar in terms of average speed and heart rate (P > 0.05). Predicted and session exertion results indicated that the steady exercise bout was perceived as easier than many trials of varied speed (P < 0.05). Trials including an intense segment in the middle or end of the session were perceived as more difficult than sessions that varied intensity otherwise or remained constant. Similarly, trials that remained constant during the 30-minute period were perceived as less aversive than most other trials. These findings suggest that exercise sessions involving a steady intensity throughout are viewed as less taxing than sessions with variable intensity, especially when compared to sessions that conclude with a higher intensity finish.     

Effects of acute 60 and 80% VO2max bouts of aerobic exercise on state anxiety of women of different age groups across time

The purpose of this investigation was to study the effects of an acute bout of aerobic exercise on state anxiety of women while controlling for iron status (hemoglobin and serum ferritin). Participants were 24 active women, ages 18-20 years (n = 12) and 35-45 years (n = 12). In addition to a nonexercise control condition, participants completed one exercise bout at 60% maximal oxygen uptake (VO2max) and one at 80% VO2max. Each exercise session consisted of a 33-min bout in which participants exercised at their target intensities for a 20-min segment. Immediately before each exercise trial, participants were given the Spielberger State Anxiety Inventory (SAI). The SAI was again administered immediately following the exercise session and at 30, 60, and 90 min postexercise. Data were analyzed using an Age x Intensity x Time (2 x 3 x 5) repeated measures analysis of covariance (ANCOVA) with iron status serving as the covariate. The ANCOVA on state anxiety yielded significant effects for time (p < .0001, eta2(p) = .48), the Intensity x Time interaction (p = .0006, eta2(p) = .19), and the Intensity x Age interaction (p = .04, eta2(p) = .15). All three exercise conditions (including control) showed a decline in state anxiety across time, but the 80% VO2max condition showed a sharper decline. Intensity of exercise conditions did not differ in state anxiety at baseline or immediately after exercise, but a difference favoring the 80% VO2max condition over the control condition emerged at 30 min postexercise. After controlling for iron status, older women who exercised at 80% VO2max exhibited lower SAI scores compared to the control condition.     

Exercise-induced hypoalgesia: Pain tolerance,preference and tolerance for exercise intensity,and physiological correlates following dynamic circuit resistance exercise

Previous research has demonstrated significant decreases in pain perception in healthy individuals following both aerobic and upper body resistance exercise, but research on circuit training has been limited. The purpose of the study was to determine the effects of a strenuous bout of dynamic circuit resistance exercise on pain threshold and pain tolerance in conjunction with changes in blood lactate levels, heart rate (HR), and perceived exertion. A sample of 24 college-age students participated in 2 sessions: (1) a maximal strength testing session and (2) a circuit training bout of exercise that consisted of 3 sets of 12 repetitions with a 1:1 work to rest ratio at 60% one-repetition maximum (1-RM) predicted from a three-repetition maximum (3-RM) for 9 exercises. Participants exhibited increases in pain tolerance, blood lactate levels, HR and perceived exertion following resistance exercise. Preference for exercise intensity was positively correlated with lactate post exercise and tolerance for exercise intensity was positively correlated with pain tolerance and lactate post exercise. In conclusion, this is the first study to demonstrate increases in pain tolerance following a dynamic circuit resistance exercise protocol and disposition for exercise intensity may influence lactate and pain responses to circuit resistance exercise.     

Effects of different exercise intensities with isoenergetic expenditures on C-reactive protein and blood lipid levels

We investigated the effects of different exercise intensities on C-reactive protein (CRP), and whether changes in CRP levels correlated with blood lipid levels. Ten men exercised at 25%, 65%, and 85% of their maximum oxygen consumption rates. Participants' blood was analyzed for CRP and blood lipid levels before and after the exercise sessions. Although there was an intensity effect for postexercise high-density lipoprotein levels, there were no significant differences or correlations for postexercise CRP levels or between CRP and lipid levels across the three exercise intensities. In an acute aerobic bout model with isoenergetic expenditures, CRP was not affected by the exercise intensity. Additionally, changes in blood lipid levels might not have been connected to CIRP levels for physically fit participants.     

Effects of exercise intensity and duration on the excess post-exercise oxygen consumption

Recovery from a bout of exercise is associated with an elevation in metabolism referred to as the excess post-exercise oxygen consumption (EPOC). A number of investigators in the first half of the last century reported prolonged EPOC durations and that the EPOC was a major component of the thermic effect of activity. It was therefore thought that the EPOC was a major contributor to total daily energy expenditure and hence the maintenance of body mass. Investigations conducted over the last two or three decades have improved the experimental protocols used in the pioneering studies and therefore have more accurately characterized the EPOC. Evidence has accumulated to suggest an exponential relationship between exercise intensity and the magnitude of the EPOC for specific exercise durations. Furthermore, work at exercise intensities >or=50-60% VO2max stimulate a linear increase in EPOC as exercise duration increases. The existence of these relationships with resistance exercise at this stage remains unclear because of the limited number of studies and problems with quantification of work intensity for this type of exercise. Although the more recent studies do not support the extended EPOC durations reported by some of the pioneering investigators, it is now apparent that a prolonged EPOC (3-24 h) may result from an appropriate exercise stimulus (submaximal: >or=50 min at >or=70% VO2max; supramaximal: >or=6 min at >or=105% VO2max). However, even those studies incorporating exercise stimuli resulting in prolonged EPOC durations have identified that the EPOC comprises only 6-15% of the net total oxygen cost of the exercise. But this figure may need to be increased when studies utilizing intermittent work bouts are designed to allow the determination of rest interval EPOCs, which should logically contribute to the EPOC determined following the cessation of the last work bout. Notwithstanding the aforementioned, the earlier research optimism regarding an important role for the EPOC in weight loss is generally unfounded. This is further reinforced by acknowledging that the exercise stimuli required to promote a prolonged EPOC are unlikely to be tolerated by non-athletic individuals. The role of exercise in the maintenance of body mass is therefore predominantly mediated via the cumulative effect of the energy expenditure during the actual exercise.     

Effects of Different Exercise Intensities With Isoenergetic Expenditures on C-Reactive Protein and Blood Lipid Levels

We investigated the effects of different exercise intensities on C-reactive protein (CRP), and whether changes in CRP levels correlated with blood lipid levels. Ten men exercised at 25%, 65%, and 85% of their maximum oxygen consumption rates. Participants' blood was analyzed for CRP and blood lipid levels before and after the exercise sessions. Although there was an intensity effect for postexercise high-density lipoprotein levels, there were no significant differences or correlations for postexercise CRP levels or between CRP and lipid levels across the three exercise intensities. In an acute aerobic bout model with isoenergetic expenditures, CRP was not affected by the exercise intensity. Additionally, changes in blood lipid levels might not have been connected to CRP levels for physically fit participants.     

The acute effects of resistance exercise on the main determinants of blood rheology

The aim of this study was to examine short-term changes in blood rheological variables after a single bout of resistance exercise. Twenty-one healthy males completed three sets of 5 - 7 repetitions of six exercises at an intensity corresponding to 80% of one-repetition maximum (1-RM). The average duration of the exercise bout was 35 min. Venous blood samples were obtained before exercise, immediately after exercise and after 30 min of recovery and analysed for lactate, red blood cell count, haematocrit, haemoglobin, plasma viscosity, fibrinogen, total protein and albumin concentration. Plasma volume decreased 10.1% following resistance exercise. This occurred in parallel with an increase of 5.6%, 5.4% and 6.2% in red blood cell count, haemoglobin and haematocrit; respectively. Plasma viscosity increased from 1.55 +/- 0.01 to 1.64 +/- 0.01 mPa s immediately after resistance exercise before decreasing to 1.57 +/- 0.01 mPa s at the end of the recovery period. Similarly, fibrinogen, albumin and total protein increased significantly following resistance exercise. However, the rises in all these rheological parameters were transient and returned to pre-exercise values by the end of recovery. We conclude that a single session of heavy resistance exercise performed by normal healthy individuals alters blood rheological variables and that these changes are transient and could be attributed to exercise-induced haemoconcentration.     

Effects of Aerobic Exercise on Cognitive Performance Among Young Adults in a Higher Education Setting

Purpose: Acute benefits of aerobic exercise on executive functioning have been reported frequently under laboratory conditions. However, to date, a beneficial effect on long-term memory has been less well supported and no data are available regarding nonlaboratory conditions in young adults. The aim of the current study was to investigate acute effects of aerobic exercise on cognitive functioning in a university classroom setting. Method: Using a cross-over design, 51 participants performed a bout of moderately intense running (RUN) and read an article while seated (CON). Afterwards, they completed free-recall tests, followed by a Flanker task and an n-back task. Results: Participants in the RUN condition compared with those in the CON condition showed shorter reaction time on the inhibition task, F(1, 50) = 5.59, p = .022, η² = .101, and recalled more words in the immediate- and delayed-recall tests, F(1, 50) = 8.40, p = .006, η² = .144. Conclusion: The present findings suggest that a moderately intense bout of aerobic exercise benefits verbal short-term and long-term memory as well as inhibitory control among students in a classroom setting.     

瘦素(Leptin)与体力活动的研究综述

L eptin是 ob基因表达的脂肪组织源激素 ,其主要作用是减少体脂、控制体重和调节机体能量平衡。它的产生和代谢受到遗传和体内外环境因素的调控和影响。运动训练可减低 ob m RNA的表达和血 leptin浓度 ,训练所致的体脂量下降是产生这种作用的重要决定因素。单次运动对 lepin表达和其血中浓度的效应 ,有减低与无影响的研究结果。运动的这些效应可能依赖于运动负荷量和热能消耗量 ,也与一些激素和代谢物有关。     

Effects of an acute bout of exercise on serum soluble leptin receptor (sOB-R) levels

Abstract

We investigated the effects of an acute bout of exercise on serum soluble leptin receptor (sOB-R) concentrations. Eighteen male participants completed two different exercise sessions with intensities of 25% and 65% maximal aerobic capacity (VO₂max). In addition to the energy expenditure during exercise sessions being measured, blood samples were collected before exercise, and immediately, at 24 h, and at 48 h post-exercise to analyse sOB-R, leptin and insulin levels. At 24 h post-exercise, sOB-R and leptin concentrations at the 65% VO₂max were significantly different from those at the 25% VO₂max. Leptin levels at 48 h post-exercise were also significantly lower for the 65% VO₂max than for the 25% VO₂max (P < 0.01). In the 65% VO₂max session, the energy expenditure during exercise was significantly associated with leptin concentrations at 24 h and 48 h and sOB-R concentrations at 24 h post-exercise. However, no correlations were found between sOB-R and leptin at the three post-exercise time points. In conclusion, an acute bout of exercise with 920 kcal of output resulted in an increase in sOB-R levels at 24 h post-exercise. However, the changes in sOB-R levels due to an acute bout of exercise might not contribute to the delayed decrease observed for leptin.     

The acute effects of resistance exercise on the main determinants of blood rheology

The aim of this study was to examine short-term changes in blood rheological variables after a single bout of resistance exercise. Twenty-one healthy males completed three sets of 5?–?7 repetitions of six exercises at an intensity corresponding to 80% of one-repetition maximum (1-RM). The average duration of the exercise bout was 35?min. Venous blood samples were obtained before exercise, immediately after exercise and after 30?min of recovery and analysed for lactate, red blood cell count, haematocrit, haemoglobin, plasma viscosity, fibrinogen, total protein and albumin concentration. Plasma volume decreased 10.1% following resistance exercise. This occurred in parallel with an increase of 5.6%, 5.4% and 6.2% in red blood cell count, haemoglobin and haematocrit; respectively. Plasma viscosity increased from 1.55?±?0.01 to 1.64?±?0.01 mPa?·?s immediately after resistance exercise before decreasing to 1.57?±?0.01 mPa?·?s at the end of the recovery period. Similarly, fibrinogen, albumin and total protein increased significantly following resistance exercise. However, the rises in all these rheological parameters were transient and returned to pre-exercise values by the end of recovery. We conclude that a single session of heavy resistance exercise performed by normal healthy individuals alters blood rheological variables and that these changes are transient and could be attributed to exercise-induced haemoconcentration.     

Influence of biological sex and exercise on murine cardiac metabolism

Although the structural and functional effects of exercise on the heart are well established, the metabolic changes that occur in the heart during and after exercise remain unclear. In this study, we used metabolomics to assess time-dependent changes in the murine cardiac metabolome following 1 session of treadmill exercise. After the exercise bout, we also recorded blood lactate, glucose, and ketone body levels and measured cardiac mitochondrial respiration. In both male and female mice, moderate- and high-intensity exercise acutely increased blood lactate levels. In both sexes, low- and moderate-intensity exercise augmented circulating 3-hydroxybutryrate levels immediately after the exercise bout; however, only in female mice did high-intensity exercise increase 3-hydroxybutyrate levels, with significant increases occurring 1 h after the exercise session. Untargeted metabolomics analyses of sedentary female and male hearts suggest considerable sex-dependent differences in basal cardiac metabolite levels, with female hearts characterized by higher levels of pantothenate, pyridoxamine, homoarginine, tryptophan, and several glycerophospholipid and sphingomyelin species and lower levels of numerous metabolites, including acetyl coenzyme A, glucuronate, gulonate, hydroxyproline, prolyl-hydroxyproline, carnosine, anserine, and carnitinylated and glycinated species, as compared with male hearts. Immediately after a bout of treadmill exercise, both male and female hearts had higher levels of corticosterone; however, female mice showed more extensive exercise-induced changes in the cardiac metabolome, characterized by significant, time-dependent changes in amino acids (e.g., serine, alanine, tyrosine, tryptophan, branched-chain amino acids) and the ketone body 3-hydroxybutyrate. Results from experiments using isolated cardiac mitochondria suggest that high-intensity treadmill exercise does not acutely affect respiration or mitochondrial coupling; however, female cardiac mitochondria demonstrate generally higher adenosine diphosphate sensitivity compared with male cardiac mitochondria. Collectively, these findings in mice reveal key sex-dependent differences in cardiac metabolism and suggest that the metabolic network in the female heart is more responsive to physiological stress caused by exercise.     

Fluid and electrolyte needs for preparation and recovery from training and competition

For a person undertaking regular exercise, any fluid deficit that is incurred during one exercise session can potentially compromise the next exercise session if adequate fluid replacement does not occur. Fluid replacement after exercise can, therefore, frequently be thought of as hydration before the next exercise bout. The importance of ensuring euhydration before exercise and the potential benefits of temporary hyperhydration with sodium salts or glycerol solutions are also important issues. Post-exercise restoration of fluid balance after sweat-induced dehydration avoids the detrimental effects of a body water deficit on physiological function and subsequent exercise performance. For effective restoration of fluid balance, the consumption of a volume of fluid in excess of the sweat loss and replacement of electrolyte, particularly sodium, losses are essential. Intravenous fluid replacement after exercise has been investigated to a lesser extent and its role for fluid replacement in the dehydrated but otherwise well athlete remains equivocal.     

Fluid and electrolyte needs for preparation and recovery from training and competition

For a person undertaking regular exercise, any fluid deficit that is incurred during one exercise session can potentially compromise the next exercise session if adequate fluid replacement does not occur. Fluid replacement after exercise can, therefore, frequently be thought of as hydration before the next exercise bout. The importance of ensuring euhydration before exercise and the potential benefits of temporary hyperhydration with sodium salts or glycerol solutions are also important issues. Post-exercise restoration of fluid balance after sweat-induced dehydration avoids the detrimental effects of a body water deficit on physiological function and subsequent exercise performance. For effective restoration of fluid balance, the consumption of a volume of fluid in excess of the sweat loss and replacement of electrolyte, particularly sodium, losses are essential. Intravenous fluid replacement after exercise has been investigated to a lesser extent and its role for fluid replacement in the dehydrated but otherwise well athlete remains equivocal.     

少年和成年业余长跑运动员急性耐力运动后心脏自主神经恢复观察研究

目的:观察少年和成年男子业余跑运动员一次急性耐力运动后心率变异(HRV)变化特征,并探讨运动后HRV变化生理学意义。方法:少年(14.4±1.3岁)与成年(25.7±2.8岁)受试者各10名,进行1次90min、强度为95%个体无氧阈强度跑台运动。在运动前、运动后15min以及运动后6h测定HRV。结果:运动后15min,TPLn、HFnu和HRV各时域指标明显低于运动前水平,LFnu和LF/HF显著升高;少年受试者HFnu降幅、LFnu和LF/HF升幅明显低于成年受试者(P<0.05)。运动后6h,HRV各指标均已恢复,其中,TPLn、SDNN、HFnu和RMSSD有反弹的迹象。运动后HFnu相对运动前的降幅与受试者年龄呈负相关关系(r=-0.645,P<0.01,n=20);另外,HFnu、TPLn相对运动前降低程度与运动前水平高度负相关(P<0.05,n=20)。结论:一次急性耐力运动后HRV出现短暂抑制现象,少年受试者运动后HRV降低幅度相对成年较低,可能与发育成熟度不同有关,急性运动后HRV变化可能是运动适应的生理表现。     

长期有氧运动一次性运动和瘦素

本文综述了当前运动对Lepfin效应的主要研究工作。Lepfin是近年发现的能量平衡调节的激素，是Ob基因的表达产物。运动对Leptin水平的影响表现在：长期有氧运动可降低血Lepfin浓度，减少脂肪组织Ob基因的表达，而一次性运动对Lepdn表达和其血中浓度的影响研究结果不一。运动的这些效应可能依赖于运动负荷量和运动时间。