Sweat lactate response during cycling at 30°C and 18°C WBGT

Sweat lactate reflects eccrine gland metabolism. However, the metabolic tendencies of eccrine glands in a hot versus thermoneutral environment are not well understood. Sixteen male volunteers completed a maximal cycling trial and two 60-min cycling trials [30°C?=?30±1°C and 18°C?=?18±1°C wet bulb globe temperature (WBGT)]. The participants were requested to maintain a cadence of 60 rev?·?min^?1 with the intensity individualized at ～ 90% of the ventilatory threshold. Sweat samples at 10, 20, 30, 40, 50 and 60?min were analysed for lactate concentration. Sweat rate at 30°C (1380±325?ml?·?h^?1) was significantly greater (P<0.05) than at 18°C (632±311?ml?·?h^?1). Sweat lactate concentration was significantly greater (P<0.05) at each time point during the 18°C trial, with values between trials tending to converge across time. During the 30°C trial, both heart rate (20, 30, 40, 50 and 60?min) and rectal temperature (30, 40, 50 and 60?min) were significantly higher than in the 18°C trial. Higher sweat lactate concentrations coupled with lower sweat rates may indicate a greater relative contribution of oxygen-independent metabolism within eccrine glands during exercise at 18°C. Decreases in sweat lactate concentration across time suggest either greater dilution due to greater sweat volume or increased reliance on aerobic metabolism within eccrine glands. The convergence of lactate concentrations between trials may indicate that time-dependent modifications in sweat gland metabolism occur at different rates contingent partially on environmental conditions.     

Comparison of the validity of four fall-related psychological measures in a community-based falls risk screening

We examined the measurement properties offall-related psychological instruments with a sample of 133 older adults (M age = 74.4 years, SD = 9.4). Measures included the Comprehensive Falls Risk Screening Instrument, Falls-efficacy Scale-International (FES-I), Activities-specific Balance Confidence (ABC), modified Survey ofActivities and Fear ofFalling in the Elderly (mSAFFE), Consequences of Falling (CoF), Physical Activity Scale for the Elderly (PASE), and 36-Item Short-Form Health Survey (SF-36). The FES-I, ABC, mSAFFE, and CoF were significantly correlated with each othe, with SF-36, and with mobility. The ABC and mSAFFE were significantly correlated with PASE. The ABC differentiated between fallers and nonfallers and predicted total falls risk. Findings can assist with the selection of psychological instruments in a falls risk screening context.     

Comparison of the Validity of Four Fall-Related Psychological Measures in a Community-Based Falls Risk Screening

Abstract

We examined the measurement properties of fall-related psychological instruments with a sample of 133 older adults (M age = 74.4 years, SD = 9.4). Measures included the Comprehensive Falls Risk Screening Instrument, Falls-efficacy Scale-International (FES-I), Activities-specific Balance Confidence (ABC), modified Survey of Activities and Fear of Falling in the Elderly (mSAFFE), Consequences of Falling (CoF), Physical Activity Scale for the Elderly (PASE), and 36-Item Short-Form Health Survey (SF-36). The FES-I, ABC, mSAFFE, and CoF were significantly correlated with each other, with SF-36, and with mobility. The ABC and mSAFFE were significantly correlated with PASE. The ABC differentiated between fallers and nonfallers and predicted total falls risk. Findings can assist with the selection of psychological instruments in a falls risk screening context.