Search Results

You are looking at 1 - 3 of 3 items for

  • Author: Felipe P. Carpes x
Clear All Modify Search
Open access

Emmanuel S. da Rocha, Álvaro S. Machado, Pedro S. Franco, Eliane C. Guadagnin and Felipe P. Carpes

Abstract

Purpose. To evaluate gait asymmetry during obstacle crossing by young and elderly adults performing normal and dual-task gait. Methods. Ten healthy young adults and ten elderly adults with mild cognitive impairment performed a gait protocol by stepping over a foam obstacle during normal gait and while performing a secondary task (Stroop task). Sagittal kinematics of the lead and trail limbs were analyzed. Statistical procedures involved analysis of variance and t tests at a significance of 0.05. Results. Many of the kinematic variables presented a main effect for group (young adults vs. elderly adults), where the elderly featured poorer gait performance. It was observed that gait velocity during obstacle crossing in normal and dual-task gait was similar between the preferred and non-preferred limbs in both the young and elderly. However, the elderly were slower during normal and dual-task gait. A main effect for the dual-task condition was observed. Kinematic asymmetries for obstacle crossing were more frequent in the elderly and especially during the dual-task condition. Conclusions. The results suggest that the elderly may require more compensatory adjustments after crossing an obstacle. The asymmetries observed among the elderly may contribute to higher risk of falling during perturbed gait.

Open access

Jose I. Priego, Rodrigo R. Bini, F.J. Lanferdini and Felipe P. Carpes

Abstract

Purpose. Despite the volume of studies addressing muscle activation during pedaling, it is unclear whether changes in workload level during cycling could dictate motor unit recruitment. The present study investigated the frequency content of lower limb muscle activation during submaximal workloads. Methods. Twelve male competitive cyclists pedaled at three workload levels: (1) maximum aerobic power output (POMAX), (2) first ventilatory threshold (POVT1), and (3) second ventilatory threshold (POVT2). Muscle activation was recorded from the right vastus medialis (VM), rectus femoris (RF), long head of biceps femoris (BF), tibialis anterior (TA), gastrocnemius medialis (GM), and soleus (SOL) muscles. Data from muscle activation were assessed using frequency band analysis. High and low frequencies and overall muscle activation were normalized to that collected at POMAX. Results. Greater overall activation was observed for VM (27%, p < 0.01, d = 1.22), RF (24%, p < 0.01, d = 0.96), BF (33%, p < 0.01, d = 1.43), GM (10%, p < 0.05, d = 0.91), and SOL (16%, p < 0.05, d = 0.81) at POVT2 than POVT1. No differences were observed in the high or low frequencies relative to overall muscle activation. Conclusions. Cyclists sustain changes at submaximal workloads via an equally distributed increase in muscle activation with no potential changes in motor unit recruitment.

Open access

Jose Ignacio Priego Quesada, Marcos R. Kunzler, Emmanuel S. da Rocha, Álvaro S. Machado and Felipe P. Carpes

Abstract

Purpose. Increased contact pressure and skin friction may lead to higher skin temperature. Here, we hypothesized a relationship between plantar pressure and foot temperature. To elicit different conditions of stress to the foot, participants performed running trials of barefoot and shod running. Methods. Eighteen male recreational runners ran shod and barefoot at a self-selected speed for 15 min over different days. Before and immediately after running, plantar pressure during standing (via a pressure mapping system) and skin temperature (using thermography) were recorded. Results. No significant changes were found in plantar pressure after barefoot or shod conditions (p > 0.9). Shod running elicited higher temperatures in the forefoot (by 0.5-2.2°C or 0.1-1.2% compared with the whole foot, p < 0.01) and midfoot (by 0.9-2.4°C, p < 0.01). Barefoot running resulted in higher temperature variation in the rearfoot (0.1-10.4%, p = 0.04). Correlations between skin temperature and plantar pressure were not significant (r < 0.5 and r > -0.5, p > 0.05). Conclusions. The increase in temperature after the shod condition was most likely the result of footwear insulation. However, variation of the temperature in the rearfoot was higher after barefoot running, possible due to a higher contact load. Changes in temperature could not predict changes in plantar pressure and vice-versa.