Aim: Mental fatigue (MF) has been defined as a psychobiological state commonly caused by prolonged periods of demanding cognitive activity. However, the differences between women and men in their reaction times (RTs) to visual stimuli due to mental fatigue remain largely unknown. We compare the differences in RT and heart rate after an acute intervention of mental fatigue between male and female athletes. Materials and methods: For this aim, 64 participants (age 31.7 ± 6.2 y) performed a routine of 15 min of the Stroop test (PsyTool), with 600 tasks and five different colors. Their heart rate (HR) was registered before, during, and one, three, and five minutes after the Stroop test. Meanwhile, the RT was evaluated before and after the Stroop test. A general linear mixed model (GLMM) and a Bonferroni post hoc test were used to compare the HR between the conditions and an ANOVA two-way analysis was used to compare the values pre-/post-Stroop test. (α = 0.05). Results: The GLMM for HR showed an effect on the time (p < 0.001) and the time × group interaction (p = 0.004). The RT was significantly increased pre- to post-Stroop test (p < 0.05); however, there was no difference between the pre- and post-HR measurements (p = 1.000) and the measurements one (p = 0.559), three (p = 1.000) and five (p = 1.000) min after the Stroop test. Conclusion: The present findings suggest that the parasympathetic branch of the autonomous nervous system which functions as a relaxation system tends to be activated under increasing mental fatigue, with a decreased performance (RT) similarly in men and women. Therefore, athletes could use MF induced during training to improve the time delay related to motor tasks.
Background: Individuals with Parkinson’s disease (PD) exhibit different combinations of motor symptoms. The most frequent subtypes are akinetic-rigid (AK-R) and hyperkinetic (HYP). Motor symptoms, such as rigidity and bradykinesia, can directly affect postural adjustments and performance in daily tasks, like gait initiation and obstacles negotiation, increasing the risk of falls and functional dependence.Objective: To compare postural adjustments and biomechanical parameters during the gait initiation and obstacle negotiation of people with AK-R and HYP PD and correlate with functional mobility and risk of falls.Methods: Cross-sectional study. Thirty-three volunteers with PD were divided into two groups according to clinical motor manifestations: AK-R (n = 16) and HYP (n = 17). We assessed the anticipatory (APA), compensatory (CPA) postural adjustments analyzing kinematic, kinetic and, electromyographic parameters during the gait initiation and obstacle negotiation tests. We applied independent T-tests and Pearson correlation tests for comparisons and correlations, respectively (α = 0.05).Results: In the APA phase of the gait initiation test, compared to the functional HYP group, the AK-R group showed shorter time for single support (p = 0.01), longer time for double support (p = 0.01) accompanied by a smaller first step (size, p = 0.05; height, p = 0.04), and reduced muscle activation of obliquus internus (p = 0.02). Similarly, during the first step in the obstacle negotiation test, the AK-R group showed less step height (p = 0.01) and hip excursion (p = 0.02), accompanied by a reduced mediolateral displacement of the center of pressure (p = 0.02) during APA, and activation of the gluteus medius (p = 0.02) and the anterior tibialis (p = 0.04) during CPA in comparison with HYP group.Conclusion: The findings suggest that people with AK-R present impaired postural adjustments during gait initiation and obstacles negotiation compared to hyperkinetic PD. Based on defined motor symptoms, the proposition presented here revealed consistent postural adjustments during complex tasks and, therefore, may offer new insights onto PD motor evaluation and neurorehabilitation.
Individuals with Parkinson’s disease (PD) have gait asymmetries, and exercise therapy may reduce the differences between more and less affected limbs. The Nordic walking (NW) training may contribute to reducing the asymmetry in upper and lower limb movements in people with PD. We compared the effects of 11 weeks of NW aerobic training on asymmetrical variables of gait in subjects with mild PD. Fourteen subjects with idiopathic PD, age: 66.8 ± 9.6 years, and Hoehn and Yard stage of 1.5 points were enrolled. The kinematic analysis was performed pre and post-intervention. Data were collected at two randomized walking speeds (0.28 m·s−1 and 0.83 m·s−1) during five minutes on the treadmill without poles. The more affected and less affected body side symmetries (threshold at 5% between sides) of angular kinematics and spatiotemporal gait parameters were calculated. We used Generalized Estimating Equations with Bonferroni post hoc (α = 0.05). Maximal flexion of the knee (p = 0.007) and maximal abduction of the hip (p = 0.041) were asymmetrical pre and became symmetrical post NW intervention. The differences occurred in the knee was less affected and the hip was more affected. We concluded that 11 weeks of NW training promoted similarities in gait parameters and improved knee and hip angular parameters for PD subjects.
Detecting the physiological and biomechanical alterations in shallow water walking (SWW) due to water depth and speed is important for health professionals to perform accurate exercise prescription. This systematic review with meta-analysis aimed to investigate the acute physiological and biomechanical responses of SWW at different immersion depths in comparison to dry land walking. The main result (initial search: 1960 studies; systematic review: 42 studies; meta-analysis: 22 studies) indicated that metabolic power was higher in the immersion depth levels of xiphoid process (standardized mean differences (SMD) = 0.90; 95% confidence intervals (CI): 0.26 to 1.54) and waist (SMD = 3.35; 95% CI: −0.18 to 6.87) in comparison to dry land. SWW at xiphoid and waist depths seems to be an adequate exercise if the objective is to increase the energy expenditure and cardiovascular demand while the lower limb impact forces are reduced in comparison to dry land walking. PROSPERO registration: CRD42018113040.