Effect of intermittent isometric handgrip exercise protocol with short exercise duration on cognitive performance

The handgrip exercise, a small muscle exercise, is useful for exercise therapy, particularly in the elderly and bedridden patients. The isometric handgrip (IHG) exercise has been utilized in training programs to reduce resting blood pressure; however, the acute effects of the IHG exercise on cognitive performance are not fully understood. The present study aimed to investigate the effect of an intermittent IHG exercise protocol with short exercise duration, which minimizes the arterial blood pressure response to exercise, on cognitive performance. Twenty-two young healthy subjects performed the intermittent IHG exercise protocol, which consisted of 30-s IHG and 45-s recovery × 16 trials; the exercise intensity of the IHG exercise was 30% of the maximal voluntary contraction. Cognitive performance was evaluated before and after the exercise with the Go/No-Go and memory recognition tasks. Specifically, the reaction time (RT) and performance accuracy were measured. The intermittent IHG exercise protocol did not change the RT or performance accuracy of either the Go/No-Go task (P = 0.222 and P = 0.260, respectively) or the memory recognition task (P = 0.427 and P = 0.245, respectively). These findings suggest that the intermittent IHG exercise protocol with short exercise duration may not provide enough stimulation to improve cognitive performance despite being useful as a safe exercise therapy in the elderly and in patients with cardiovascular disease.

A caffeine containing weight loss supplement augments hemodynamic responses after exercise

BACKGROUND

Since the effects of supplements can be potentially harmful and/or ineffective to obtain desired positive benefits, there is a need to investigate supplementation to understand the responses of physiological systems, to educate consumers, and to provide feedback for businesses creating these supplements. The purpose of the current study was to test hemodynamic responses of a weight loss supplement and determine its effects on hemodynamic variables.

METHODS

31 participants underwent a randomized, double-blind, crossover study design and received a placebo or supplement on two separate days. Baseline measures of all variables were assessed prior to exercise. During exercise, each participant performed treadmill running at 80% VO_2PEAK until volitional fatigue. Immediately post-exercise, hemodynamic measures were recorded at multiple time points.

RESULTS

There was a significant condition∗time interaction with the supplement having a higher PWV for the carotid to femoral segment (p=0.004). There were also significant condition∗time interactions for heart rate (p=0.001). Large arterial elasticity was significantly lower for the supplement (p=0.005). Systolic blood pressure was conditionally higher (p=0.001), as was diastolic blood pressure (p=0.003) and mean arterial pressure (p=0.003). Vascular resistance was conditionally higher for the supplement (p=0.044).

CONCLUSIONS

Ingredients in the supplement caused multiple negative effects within hemodynamics and were ineffective at increasing running time.