Effects of a prolonged run on simple reaction time of well trained runners.

The aim of the present study was to examine the effect of increased arousal induced by a prolonged exercise at ventilatory threshold simple reaction time performance performed during a running task. 11 well trained triathletes completed two testing sessions within a 2-wk. period. The first session was a protocol of VO2 max determination conducted on a treadmill. This protocol was used to assess the velocity associated with ventilatory threshold (vVvt). The second session was a 90-min. running test performed at vVvt. This last session was composed of five submaximal treadmill runs (10-min. long, 0% grade) separated by four overground runs (10-min.). Before, during each treadmill run, and after exercise, subjects performed three blocks of 20 simple reaction time. Furthermore, at the end of each overground run, perceived exertion (RPE) was recorded. Analysis showed a significant impairment in Simple RT performance during the first treadmill run only. After this first run a significant effect of exercise duration on Simple RT was observed. After 40-min. of exercise a significant improvement in reaction time during exercise was recorded, Furthermore, when Simple RT was recorded at rest, there was no difference pre-exercise and postexercise. These results suggest that a simple cognitive performance could be improved during exercise, despite the negative effect of the dual task. This improvement in reaction time could be explained mainly by an increase in arousal induced by a prolonged exercise.     

Twisting the night away: the effects of all night disco dancing on reaction time

8 subjects performed an unprepared simple reaction time task for 20 min. every 2 hr. while taking part in an all night disco dancing marathon (continuous exercise) and during a control (no exercise) night. Mean reaction times were significantly faster and less variable during the dance marathon. It was suggested that the effects of continuous exercise in the form of disco dancing may be to reduce drowsiness which in turn assists performance.     

Aerobic cycle exercising in a rehabilitation program with a wider choice of intensity

When patients in rehabilitation programs use cycle ergometers for aerobic fitness training, the exercise intensity is often restricted to a small range of heart rate. In this study, a wider choice of intensities was left to the patients without giving up the potential to reduce cardiac risks factors. 24 patients in 3-wk. rehabilitation programs could choose the exercise intensity up to a workload limit preset by the physical therapist. 20 of them exercised at an intensity covering the full range between the aerobic and anaerobic lactate threshold and 4 a little above. The opportunity to vary the workload was frequently used by 67%. In 75% of the exercise sessions, the patients' average heart rates exceeded moderate heart-rate targets recommended in rehabilitation and health promotion for people with moderate cardiac risks without a graded exercise test. In 72% of these sessions, the anaerobic lactate threshold at 4 mmol/L was not exceeded. But a tendency of 33% of the patients to exercise at higher blood lactate or blood pressure levels underlined the necessity of limiting the exercise intensity.     

Acute aerobic exercise and information processing: energizing motor processes during a choice reaction time task

The immediate and short-term after effects of a bout of aerobic exercise on young adults’ information processing were investigated. Seventeen participants performed an auditory two-choice reaction time (RT) task before, during, and after 40 min of ergometer cycling. In a separate session, the same sequence of testing was completed while seated on an ergometer without pedalling. Results indicate that exercise (1) improves the speed of reactions by energizing motor outputs; (2) interacts with the arousing effect of a loud auditory signal suggesting a direct link between arousal and activation; (3) gradually reduces RT and peaks between 15 and 20 min; (4) effects on RT disappear very quickly after exercise cessation; and (5) effects on motor processes cannot be explained by increases in body temperature caused by exercise. Taken together, these results support a selective influence of acute aerobic exercise on motor adjustment stage.     

The Effects of Exercise as a Countermeasure for Fatigue in Sleep-Deprived Aviators

This study examined the effectiveness of exercise for sustaining performance despite moderate amounts of sleep. Twelve volunteers engaged in 10-min bouts of exercise during one 40-hr period of sleep deprivation and rested for an equivalent amount of time during a 2nd period. Participants were more alert immediately following exercise, as evidenced by longer sleep latencies, than after the resting, control condition. However, electroencephalogram data collected 50 min following exercise or rest showed that exercise facilitated increases in slow-wave activity, signs of decreased alertness. Cognitive deficits and slowed reaction times associated with sleep loss were equivalent in both conditions. The results from this study suggest that short bouts of exercise may ameliorate some of the increases in sleepiness and fatigue associated with sleep loss for a short period of time but are not likely to prevent performance decrements. In addition, less than 1 hr following exercise, significant increases in fatigue and sleepiness may occur.     

Influence of acetaminophen consumption on perceived exertion at the lactate concentration threshold

The purpose of this investigation was to study effects of acetaminophen consumption on ratings of perceived exertion and estimated time limit responses at the lactate threshold. 98 young regional to national level athletes performed a graded exhausting exercise on an outdoor running track to estimate their maximal aerobic velocity and the velocity associated with their lactate concentration threshold. Urine (30 mL) was collected during this test and analysed for numerous substances. During urinary screening for doping substances, 9 acetaminophen consumers (9.2%) among the 98 included athletes were detected. These acetaminophen consumers have significantly lower perceived exertion at velocity corresponding to the lactate concentration threshold than nonconsumers (11.9 +/- 2.1 vs 13.6 +/- 2.1, respectively) although they were at the same relative exercise intensity. This result shows that acetaminophen consumption may have mediated the perceived exertion response at the lactate concentration threshold. This may then suggest that the pain induced by training load could be a factor in use of self-prescribed pain relievers. Such consumption must be taken into account by medical staff, trainers, or educators who have to give information on the use and adverse effects of this substance and to propose palliative methods to their athletes.     

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 effect of physical fitness training on reaction time in youth with intellectual disabilities

The purpose of this study was to assess whether reaction time in persons with intellectual disabilities can be improved with an exercise program. 50 children and adolescents (M age = 14.7 yr., SD = 1.4, range = 11-18) with mild intellectual disability without Downs syndrome were randomly divided into control (20 boys, 5 girls) and experimental (19 boys, 6 girls) groups. The experimental group participated in a structured physical fitness program for 12 weeks. Reaction time was assessed at baseline and after 12 weeks. Significant improvements in reaction time were observed in the exercise group but not for the control group. Results indicated that reaction time can be improved with an exercise program in youth with intellectual disability.     

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.     

Regulation of exercise intensity using ratings of perceived exertion during passive visual distraction

The purpose of this investigation was to determine if passive visual distraction altered ability to regulate exercise intensity as, assessed by ratings of perceived exertion during a 30-min. treadmill run. 10 trained females (VO2max, 52.7 ml.kg-1.min.-1) performed a graded exercise test on a treadmill to assess maximal aerobic power and rating of perceived exertion, oxygen uptake (VO2), heart rate, and running velocity at the 2.5 mmol.L-1 blood lactate concentration. Subjects then used the target rating of perceived exertion to regulate exercise intensity during a control condition, and two treatment runs with passive visual distractions. During the treatment sessions, the subjects ran on a treadmill while viewing a high-action or a low-action video with no audio. The subjects were allowed to adjust the treadmill speed throughout the run to maintain the target rating of perceived exertion; however, subjects were not allowed to view the speed setting. There were no significant differences in blood lactate concentration among the conditions for the control, low action, high action, or graded exercise test (p < or = .05). No significant differences in VO2 or running velocity were found within or among the 30-min. treatment runs and the graded exercise test. Heart rate at 5 min. of exercise during control (158 +/- 3 b.min.-1), low action (158 +/- 3 b.min.-1), and high action (159 +/- 2 b.min.-1) was significantly lower than the graded exercise test (169 +/- 3 b.min.-1). Based on the data collected, visual passive distraction did not alter regulation of intensity using ratings of perceived exertion during a 30-min. treadmill run.     

One year after ischemic stroke: Changes in leg movement path stability in a speed–accuracy task but no major effects on the hands

First year after the stroke is essential for motor recovery. The main motor control strategy (i.e., faster movement production at the expense of lower movement accuracy and stability, or greater movement accuracy and stability at the expense of slower movement) selected by poststroke patients during a unilateral speed–accuracy task (SAT) remains unclear. We aimed to investigate the poststroke (12 months after stroke) effects on the trade-off between movement speed and accuracy, and intraindividual variability during a motor performance task. Healthy right-handed men (n = 20; age ∼ 66 years) and right-handed men after ischemic stroke during their post rehabilitation period (n = 20; age ∼ 69 years) were asked to perform a simple reaction task, a maximal velocity performance task and a SAT with the right and left hand, and with the right and left leg. In the hand movement trial, reaction time and movement velocity (V_max) in the SAT were slower and time to V_max in the SAT was longer in the poststroke group (P < .01). In the leg movement trial, poststroke participants reached a greater V_max in the SAT than the healthy participants (P < .01). The greatest poststroke effect on intraindividual variability in movements was found for movement path in the SAT, which was significantly greater in the legs than in the hands. Poststroke patients in the first year after stroke mainly selected an impulsive strategy for speed over hand and leg motor control, but at the expense of lower movement accuracy and greater variability in movement.     

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.     

Sex differences in psychological effects of exercise

The purpose of this study was to investigate sex differences in psychological effects of exercise on university students. University students (73 female and 65 male) were randomly assigned to experimental and control groups by equating sex in each group. The experimental group participated in step dance sessions of 50 min per day, 3 days per week for 10 weeks with 60-80% of their heart rate reserves. Throughout the 10-week period, the lecture control group was told not to participate in any organized or structured exercise and participated in a lecture that was about the physiological and psychological benefits of exercise. Self-concept, belief in external control, and trait anxiety of the groups were measured before and after the exercise program. A significant improvement in the psychological variables after the exercise program and more improvement for female exercise participants were expected. Analysis revealed no significant initial differences in self-concept, belief in external control, and trait anxiety between the two groups or between males and females, other than family and moral/ethical self. Repeated measures analysis of variance revealed that exercise led to less belief in external control and significant improvement in physical self and identity dimensions of self-concept for the experimental group compared to the control group. However, there was no significant difference in trait anxiety between the two groups after exercise (p>.05). Analysis also revealed that changes in belief in external control, trait anxiety, and self-concept did not differ with regard to sex. Males and females showed no difference in their improvement on trait anxiety, belief in external control, and most dimensions of self-concept during the 10 weeks. Only changes in personal and physical self throughout 10-week period were different for males and females. Exerciser males improved their personal self and physical self scores more than female exercisers and male and female nonexercisers throughout the 10-week period (p<.05).     

Effects of fatigue induced by repetitive movements and isometric tasks on reaction time

PurposeThe understanding of fatigue of the human motor system is important in the fields of ergonomics, sport, rehabilitation and neurology. In order to understand the interactions between fatigue and reaction time, we evaluated the effects of two different fatiguing tasks on reaction time.Methods83 healthy subjects were included in a case-control study with three arms where single and double choice reaction time tasks were performed before and after 2 min fatiguing task (an isometric task, a finger tapping task and at rest).ResultsAfter an isometric task, the right-fatigued hand was slower in the choice component of a double choice reaction time task (calculated as the individual difference between single and double choice reaction times); also, the subjects that felt more fatigued had slower choice reaction time respect to the baseline assessment. Moreover, in relationship to the performance decay after two minutes, finger tapping task produces more intense fatigability perception.ConclusionsWe confirmed that two minutes of isometric or repetitive tasks are enough to produce fatigue. The fatigue perception is more intense for finger tapping tasks in relation to the performance decay. We therefore confirmed that the two fatiguing tasks produced two different kind of fatigue demonstrating that with a very simple protocol it is possible to test subjects or patients to quantify different form of fatigue.     

The influence of exercise duration and cognitions during running on feeling states in an indoor running track environment

Objectives. To examine the influence of different durations of aerobic exercise and cognitions during running on exercise-induced feeling state changes in an indoor running track environment once baseline differences in feeling states were controlled.Method. Physically active females (n=69) participated in one of three experimental conditions: a) a 25 min run at 70% heart rate reserve (HRR), b) a 40 min run at 70% HRR, or c) a 40 min no exercise control. Pre-post feeling states (EFI) were assessed and cognitions during running were recorded with 5 min left in the run.Results. Multilevel modeling analyses revealed that positive engagement and revitalization significantly increased from pre- to post-exercise in comparison to the control condition regardless of exercise duration whereas physical exhaustion was significantly reduced. However, tranquility significantly increased only in the 25 min run condition. Finally, cognitions during exercise moderated the changes in feeling states from pre- to post-exercise above and beyond exercise duration with participants reporting dissociative-external thoughts reporting greater increases in revitalization and decreases in physical exhaustion.Conclusions. Both objective demands of the exercise task (i.e., exercise duration) and subjective intrapsychic phenomena (i.e., cognitions during running) may aid in explaining exercise-induced feeling state changes.     

A hierarchical model of approach achievement motivation and effort regulation during a 90-min. soccer match

Research indicates that effort close to the lactate threshold during a soccer match is of importance to succeed, so a prospective study was conducted and a hierarchical achievement motivation approach model tested in relation to effort reglation among 55 male high level soccer players (M=23.6 yr., SD=4.3). The motive to chieve success was expected to be positively associated with the mastery goal, which would be positively associated with playing time close to the lactate threshold in the irst soccer match period, and this positively associated with the same magnitude of effort in the second period. We also examined whether the mastery goal would medite the link between the motive to achieve success and playing time close to the lactate threshold during the first period and also playing time close to the lactate threshold in the first period would mediate the link between the mastery goal and playing time at this effort level during the second period. LISREL analyses supported these predictions. Additional hierarchical polynomial multiple regression analyses indicated unexpected significant nonlinear associations between the motive to avoid failure and effort regulation. The latter is partly explained by ideas from the catastrophe theory.     

Reaction time unchanged in older women following aerobic training

The effect of aerobic exercise on reaction time in older women was investigated. 14 women (M age = 65 yr.) were carefully screened for health status and lifestyle, then assigned to a random order of the exercise and control groups (ns = 7). Pre- and posttraining tests of aerobic capacity, simple reaction time, and choice reaction time were administered. The exercise group rode a stationary bicycle ergometer for 8 consecutive weeks for 3 35- to 40-min. sessions per week. There were no significant pretraining differences between groups on simple reaction time, choice reaction time, or estimated VO2max. No posttraining differences for simple and choice reaction time were found even though the exercise group had a significantly higher VO2max than the controls. Contrary to some other findings, the data indicate that reaction time may be independent of aerobic training in healthy older women.     

Fractioned Reaction Ttme in Power-Trained and Endurance-Trained Athletes under Conditions of Fatiguing Isometric Exercise

Fractionated knee extensor and plantar flexor reaction time (RT) components were assessed in a group of eight weightlifters and eight long distance runners. Following a 4-day period of baseline stabilization for each muscle group, a 50% maximal voluntary contraction (MVC) holding-time exercise was administered. Results showed that the runners had longer premotor times (PMT) than the weightlifters in the knee extensors, but had much faster PMTs than the lifters in the plantar flexor condition. Compared to previously reported investigations using non-athletes, the data for the present sample of athletes indicated faster total reaction times (TRT) in both the knee extensors and the plantar flexors. A resistance of 15% MVC applied during the RT task resulted in a lengthening of the motor time (MT) component in both groups prior to exercise. However, while knee extensor resisted motor time was lengthened by the exercise task, no such lengthening occurred in plantar flexor resisted RT. It is concluded that power-trained and endurance-trained athletes exhibit differences in response to a fractionated RT task, under both baseline and fatiguing exercise conditions.     

Fractioned reaction time in power-trained and endurance-trained athletes under conditions of fatiguing isometric exercise

Fractionated knee extensor and plantar flexor reaction time (RT) components were assessed in a group of eight weightlifters and eight long distance runners. Following a 4-day period of baseline stabilization for each muscle group, a 50% maximal voluntary contraction (MVC) holding-time exercise was administered. Results showed that the runners had longer premotor times (PMT) than the weightlifters in the knee extensors, but had much faster PMTs than the lifters in the plantar flexor condition. Compared to previously reported investigations using non-athletes, the data for the present sample of athletes indicated faster total reaction times(TRT) in both the knee extensors and the plantar flexors. A resistance of 15% MVC applied during the RT task resulted in a lengthening of the motor time (MT) component in both groups prior to exercise. However, while knee extensor resisted motor time was lengthened by the exercise task, no such lengthening occurred in plantar flexor resisted RT. It is concluded that power-trained and endurance-trained athletes exhibit difference in response to a fractionated RT task, under both baseline and fatiguing exercise conditions.     

The effect of choice of exercise mode on psychological responses

Objectives: Choice has been linked to both motivation and psychological responses to exercise. This paper investigates participants’ psychological responses when they completed an exercise session where there was a high-preference exercise mode as opposed to a low-preference exercise mode. High- and low-preference were established by participants indicating their preferred choice of exercise from three standard modes used for aerobic work.Method: Participants were 20 low-active adults who exercised for 20 min on each mode of exercise (high-preference versus low-preference). Affect, ratings of perceived exertion (RPE) and heart rate (HR) were recorded every 5 min during exercise, and affect and HR were assessed pre-exercise and 5 min post-exercise.Results: Repeated measures analysis of variance revealed condition and time main effects for affect sub-scales and RPE and a time main effect for HR. Affect sub-scales, RPE and HR generally increased over time. RPE, Fatigue and Psychological Distress were higher in the low-preference condition and positive well-being was higher in the high-preference condition.Conclusions: Affect and RPE were influenced by the preferred choice manipulation. Affect was more positive, and RPE lower, in the high-preference versus low-preference condition while work rate remained constant across conditions.