The Acute Effect of Exercise on Executive Function and Attention: Resistance Versus Aerobic Exercise.

Acute aerobic exercise was shown to enhance such cognitive functions as executive function (EF) and attention. Acute resistance exercise was also shown to enhance cognitive functions, however, only few studies directly compared these two exercise modalities. The aim of this study was to evaluate the acute effect of a typical moderate intensity resistance exercise session as compared to a typical moderate intensity aerobic session, on executive function and attention. A counterbalanced repeated measures experimental design was applied. Forty physical education students (21 women; 19 men, age = 25.7±2.84 years) were tested before and after three sessions: aerobic, resistance, and control. Each session consisted of 30 minutes of exercise or a rest. Executive function and attention were assessed by components of the computerized Stroop Catch game and Go-NoGo cognitive tests. A two-way ANOVA showed a greater increase in attention scores after the resistance sessions (p < .05) compared to the control condition. Attention scores in the aerobic sessions showed a trend toward improvement but did not reach statistical significance. Scores of EF significantly increased, both after the resistance session and the aerobic session (p < .05), but not after rest in the control condition. Our findings show that an acute session of resistance exercise increased both Attention and EF test scores, while an aerobic exercise session improved only the EF scores.

Effects of a Commercial Supplement of Ophiocordyceps sinensis and Ganoderma lucidum on Physiological Responses to Maximal Exercise in Healthy Young Participants.

Cordyceps sinensis (=Ophiocordyceps sinensis) and Ganoderma lucidum are 2 medicinal mushrooms that have been suggested to have the potential to enhance exercise capacity. We used a commercial supplement combining a traditional Chinese medicine and G. lucidum and tested its effects on human physical, aerobic, and anaerobic capacities. Physical education students (n = 96; 43 women, 53 men; mean ± standard deviation age, 26.3 ± 3.21 years) were randomly divided into 3 groups: low-dose treatment, high-dose treatment, and placebo. Participants received the supplement or the placebo for 28-33 days. Both before and after the intervention, the participants performed a graded maximum oxygen consumption (Vo2max) test on a treadmill and a Wingate anaerobic cycle test (on a different day). The following parameters were measured and recorded during the maximal graded treadmill test: heart rate, oxygen consumption, respiratory exchange ratio, and ventilation. The following parameters were calculated from the Wingate anaerobic cycle test: maximal anaerobic power, mean anaerobic power, and fatigue index. The supplements did not affect Vo2max or the physiological responses upon maximal exercise during the graded treadmill test. In a similar way, they had no effect on peak or mean power, or fatigue index, as measured by the Wingate anaerobic test. A borderline interaction indicated a somewhat lower heart rate at rest after treatment; however, post hoc analysis did not reveal any further statistically significant differences (P = 0.047; F = 3.169). The findings indicate that dual supplementation with C. sinensis and G. lucidum had no effect on Vo2max, on physiological responses at peak exercise load during a graded maximal treadmill test, or on the parameters of anaerobic capacity.

Clinical Effects of a Commercial Supplement of Ophiocordyceps sinensis and Ganoderma lucidum on Cognitive Function of Healthy Young Volunteers.

Ophiocordyceps sinensis (= Cordyceps sinensis) and Ganoderma lucidum are medicinal mushrooms used in traditional Chinese medicine. The effects of O. sinensis and G. lucidum on cognitive function have been evaluated through the use of animal models and in vitro studies, which indicated beneficial effects. The purpose of this study was to evaluate the effects of treatment with a commercially available supplement of O. sinensis and G. lucidum on cognitive function in young, healthy human participants. Physical education students (n = 96 [53 men, 43 women]; mean ± standard deviation age, 26.3 ± 3.21 years) were randomly divided into 3 treatment groups: highdose supplement (HD) group, low-dose supplement (LD) group, and a placebo (PL) group. Each group received the treatment, administered by a technician blinded to supplements/placebo, for 30 days. Participants were evaluated for various cognitive functions before and immediately after treatment. Evaluation of cognitive function domains-global cognitive score, memory, executive function, attention, information processing speed, visuospatial ability, verbal function, and motor skills-showed no significant differences between groups. These results indicate that a combination of O. sinensis and G. lucidum supplements for 30 days did not enhance cognitive function domains in young healthy participants.

Physiological characteristics of the preferred transition speed in racewalkers.

PURPOSE: The preferred transition speed (PTS) at which humans change their gait from walking to running was found to be lower than their energetically optimal transition speed (EOTS). This phenomenon has not been examined in racewalkers. The purpose of this study was to evaluate the PTS and the EOTS in racewalkers compared with controls. METHODS: Eleven racewalkers and 13 control subjects participated in this study. Subjects arrived at the laboratory on three occasions. Visit I: determination of PTS. Subjects walked at a slow speed that was increased by 0.2 km x h every 30 s until they felt it was easier to run. Then, subjects ran at a high speed and the treadmill speed was reduced by 0.2 km x h every 30 s until they felt it was easier to walk. Visits II and III: subjects walked and ran at PTS - 1 km x h, PTS - 0.5 km x h, PTS, PTS + 0.5 km x h, and PTS + 1 km x h. At each stage, physiological measurements were recorded. RESULTS: PTS was 7.33 +/- 0.33 km x h in controls and 8.20 +/- 0.54 km.h in racewalkers (P < 0.001), and EOTS was 8.00 +/- 0.48 km x h in controls and 8.46 +/- 0.55 km x h in racewalkers (P = 0.039). There was a trend for a smaller difference between PTS and EOTS in racewalkers. V O2 was higher during running at the PTS in both groups (F1, 22 = 5.972, P = 0.023), and there was a trend for a group interaction (F1, 22 = 3.442, P = 0.077). HR and V E were higher at the PTS in racewalkers compared with controls. CONCLUSION: Racewalkers have a higher PTS and EOTS compared with controls. There is a trend for the difference between the PTS and the EOTS to be smaller in racewalkers compared with controls.

The effect of sibutramine intake on resting and exercise physiological responses.

AIM: To evaluate the effect of a short-term sibutramine intake on energy expenditure and on physiological responses during rest, submaximal exercise and maximal exercise in obese women. METHODS: Fifteen healthy obese female volunteers were randomly assigned to either a placebo (n = 6 - control) or sibutramine group (n = 9 - experimental) under double-blind conditions. Each subject was tested under resting conditions and then performed submaximal and maximal exercise tests. Subjects were retested under identical conditions following a 5-day administration of either sibutramine 10 mg x day(-1) or a placebo. All measurements (i.e. weight, body composition, resting energy expenditure, heart rate, respiratory exchange ratio, ventilation, oxygen consumption, carbon dioxide production, systolic blood pressure, diastolic blood pressure and blood lactate concentration) were analyzed using a 2-way ANOVA with repeated measures. RESULTS: Only heart rate during submaximal exercise was significantly different (higher) following short-term sibutramine administration when compared to placebo (p < 0.05). CONCLUSIONS: These data suggest that a recommended daily dose of 10 mg sibutramine does not affect energy expenditure or other selected cardiopulmonary responses during rest, submaximal exercise or maximal exercise. It is, therefore, suggested that weight loss during sibutramine treatment in humans is achieved mostly via a decrease in energy intake rather than through an increase in energy expenditure and thermogenesis.

The effect of pre-test carbohydrate ingestion on the anaerobic threshold, as determined by the lactate-minimum test.

The purpose of this study was to investigate the effect of pre-test carbohydrate (CHO) ingestion on anaerobic-threshold assessment using the lactate-minimum test (LMT). Fifteen competitive male distance runners capable of running 10 km in 33.5-43 min were used as subjects. LMT was performed following CHO (2x300 mL, 7% solution) or comparable placebo (Pl) ingestion, in a double-blind, randomized order. The LMT consisted of two high-intensity 1 min treadmill runs (17-21 km.h(-1)), followed by an 8 min recovery period. Subsequently, subjects performed 5 min running stages, incremented by 0.6 km.h(-1) and separated by 1 min blood-sampling intervals. Tests were terminated after 3 consecutive increases in blood-lactate concentration ([La]) had been observed. Finger-tip capillary blood was sampled for [La] and blood-glucose determination 30 min before the test's onset, during the recovery phase following the 2 high-intensity runs, and following each of the subsequent 5 min stages. Heart rate (HR) and rating of perceived exertion (RPE) were recorded after each stage. The lactate-minimum speed (LMS) was determined from the individual [La]-velocity plots and was considered reflective of the anaerobic threshold. Pre-test CHO ingestion had no effect on LMS (13.19+/-1.12 km.h(-1) vs. 13.17+/-1.08 km.h(-1) in CHO and Pl, respectively), nor on [La] and glucose concentration at that speed, or on HR and RPE responses. Pre-test CHO ingestion therefore does not affect LMS or the LMT-estimated anaerobic threshold.

Preferred transition speed between walking and running: effects of training status.

PURPOSE: This study was conducted to identify the preferred transition speed (PTS) between walking and running and the energetically optimal transition speed (ETOS), in runners and nonrunners. METHODS: A total of 19 young men were asked to walk on a treadmill at 5 km.h(-1). Speed was then increased by 0.2 km.h(-1) every minute. Subjects were instructed to start running at a particular speed they felt was easier. PTS for each subject was determined as the mean of the walk-run and the run-walk transitions. Subjects were also asked to walk and to run for 5 min at each of the following velocities: PTS - 1 km.h(-1), PTS - 0.5 km.h(-1), PTS, PTS + 0.5 km.h(-1), and PTS + 1 km.h(-1). This procedure was performed twice, once walking and once running, at all speeds. Physiologic measurements of oxygen consumption, heart rate, and rate of perceived exertion (RPE) were performed at each stage. EOTS was determined by plotting individual curves for each subject with the energy cost of locomotion as a function of velocity. RESULTS: Preferred transition speed was 7.23 +/- 0.25 and 7.42 +/- 0.25 km.h(-1) for nonrunners and runners, respectively (P > 0.05), and differed significantly (F = 16.47, alpha < 0.001) from the EOTS, which was 8.02 +/- 0.84 km.h(-1) for nonrunners and 7.90 +/- 0.48 km.h(-1) for the runners. No significant differences were found between runners and nonrunners in PTS or EOTS. Running at the PTS resulted in a significantly lower RPE and higher energy cost than walking at the PTS in both groups. CONCLUSION: This study indicates that 1) the preferred PTS is slower than the EOTS, and 2) the PTS and EOTS are not dependent on the aerobic capacity or the training status.

The effects of speech production on physiologic responses during submaximal exercise.

PURPOSE: To investigate the effects of speech production on physiological responses during sub maximal exercise of various intensities. METHODS: Three constant levels running at work intensities corresponding to 65%, 75%, and 85% of the subjects' (N = 14) VO(2) max were performed with and without talking. These loads were chosen to represent the range of training intensities, which are most often used by the general population for improving cardiovascular fitness. During both sessions, various cardiopulmonary variables were measured breath-by-breath. RESULTS: Oxygen uptake, ventilation, breathing frequency, CO(2) production, total respiration cycle time, and expiration time decreased significantly while blood lactate, blood pressure, and end tidal CO(2) increased. There were no significant differences between talking and being silent in heart rate, inspiration time, and in tidal volume. CONCLUSIONS: Speech production during sub maximal exercise results in a significant reduction in minute ventilation and oxygen uptake with an accompanying elevation of lactic acid and blood pressure. These findings are of particular relevance for planning rehabilitation or training programs for ill as well as for healthy populations.