Exercise training effect on skeletal muscle motor drive in older adults: A systematic review with meta-analysis of randomized controlled trials.

The meta-analysis aimed to determine whether exercise training can positively change indices of motor drive, i.e., the input from the central nervous system to the muscle, and how training characteristics, motor drive assessment, assessed muscle, and testing specificity could modulate the changes in motor drive in older adults. A random-effect meta-analysis model using standardized mean differences (Hedges' g) determined treatment effects. Moderators (e.g., training type and intensity) and meta-regressors (e.g., number of sessions) were performed using mixed- and fixed-effect models. A significant Q-test, followed by pairwise post hoc comparisons, determined differences between levels of the categorical moderators. Methodological quality was assessed using the Cochrane risk of bias tool. Ten randomized controlled trials, 290 older adults, met the inclusion criteria. Only strength and power exercise training were retrieved from the search and included in the analysis. Strength (g = 0.60, 95 % CI 0.24 to 0.96) and power training (g = 0.51, 95 % CI 0.02 to 1.00) increased motor drive compared with a control condition. High (g = 0.66; 95 % CI 0.34 to 0.97) and low-high (g = 1.23; 95 % CI 0.19 to 2.27) combinations of training intensities increased motor drive compared to the control condition. The multi-joint training and testing exercise structure (g = 1.23; 95 % CI 0.79 to 1.67) was more effective in increasing motor drive (Qdf=2 = 14.15; p = 0.001) than the multi-single joint structure (g = 0.46; 95 % CI 0.06 to 0.85). Therefore, strength and power training with high volume and intensity associated with multi-joint training and testing combination of exercises seem to improve skeletal muscle motor drive in older adults effectively.

Caffeine Attenuates Exacerbated Central Fatigue during Moderate Intensity Cycling Exercise in Women with Fibromyalgia.

PURPOSE: To compare the development of fatigability during a moderate intensity cycling exercise between women with fibromyalgia (FM) and control women (CON) after acute ingestion of caffeine and placebo. METHODS: Ten FM and 10 CON women performed a 30-minute moderate intensity cycling exercise one hour after the ingestion of a capsule containing either caffeine or a placebo. Fatigability and its central and peripheral determinants were determined via changes from pre- to post-15 and post-30 minutes of exercise in maximal voluntary isometric contractions (MVIC), voluntary activation (VA), and quadriceps potentiated twitch torque (Q tw-pot ), respectively. Heart rate, muscle oxygen saturation, perceptive responses, mood state, localized and widespread pain, and sleepiness were also monitored during and after exercise. RESULTS: There was a time vs. group interaction for MVIC and VA (p < 0.001) but not for Q tw-pot (p = 0.363), indicating a greater rate of fatigability development, mainly caused by central mechanisms, in the FM than in the CON group. There was also a main effect of condition for VA (p = 0.011), indicating that caffeine attenuates central mechanisms of fatigability in both groups. Caffeine ingestion also increased muscle oxygenation, perceived vigor, and energy, and decreased leg muscle pain, sleepiness, and perceived fatigue in both groups. However, caffeine improved perceived pleasure/displeasure and exercise adherence likelihood only in the FM group. CONCLUSIONS: Compared to CON, women with FM present a greater rate of fatigability during exercise, mainly of central origin. Caffeine seems to be a promising bioactive to counteract the central mechanisms of fatigability and improve the exercise experience among FM women.

Complete recovery of quadriceps muscle peripheral fatigue after running in Olympic, but not Sprint, triathlon.

This study compared central and peripheral fatigue development between the Sprint and Olympic distance triathlon. Fifteen male triathletes performed Sprint and Olympic triathlon simulations in a randomized and counterbalanced order. Central and peripheral fatigue was evaluated from changes in voluntary activation level (VAL) and twitch responses of quadriceps muscle (Qtw,pot), respectively. Qtw,pot reduced from baseline to post-swimming similarly between triathlon simulations (Sprint,-17±11%; Olympic, -13±9%). In post-cycling, Qtw,pot further declined to a similar extent between triathlon distances (Sprint, -31±15%; Olympic, -28±11%). In post-running, Qtw,pot was fully recovered in the Olympic triathlon (-4±10%), whereas there was only a partial recovery of Qtw,pot in the Sprint triathlon (-20±11%). VAL was not reduced in post-swimming, but reduction was similar between triathlon distances in post-cycling (Sprint, -10±9%; Olympic, -8±8%) and post-running (Sprint, -15±14%; Olympic, -16±8%). In the Sprint triathlon, the swimming speed (1.07±0.13m.s-1) was above (p <.001) critical speed (1.01±0.14m.s-1), the cycling power (179.7±27.2W) was below the respiratory compensation point (216.3±27.8W, p <.001) and running speed (13.7±1.05km.h-1) similar to the respiratory compensation point (13.2±0.70km.h-1, p =.124). In the Olympic triathlon, swimming speed (1.03±0.13m.s-1) was similar to critical speed (p =.392), and cycling power (165.3±27.3W) and running speed (12.6±1.05km.h-1) were below the respiratory compensation point (p ≤.007). In conclusion, peripheral fatigue progressed until post-cycling regardless of triathlon distances. However, peripheral fatigue was fully recovered after running in Olympic but not in Sprint triathlon. The central fatigue started in post-cycling and progressed until post-running regardless of triathlon distances.HighlightsThe quadriceps muscle peripheral fatigue progresses similarly in Sprint and Olympic triathlons until post-cycling.The quadriceps muscle peripheral fatigue is completely recovered after running in the Olympic triathlon, whereas it is partially recovered in the Sprint triathlon.The central fatigue starts in post-cycling and progresses similarly until post-running in Sprint and Olympic triathlons, regardless of triathlon distances.

Nursing Home Residence, Overweight and Cognitive Status are Related to Falls in Older Adults: A Cross-sectional Study.

BACKGROUND: Nursing home residents are likely to differ from community older adults when their gait parameters are compared, as nursing home residents present more falls. AIM: The study aim was to identify the main fall (occurrence predictors) (anthropometrics, functional and gait-related parameters) between older adults living in community and nursing homes during self-selected (SSWS) and fast walking speeds (FWS). METHODS: A hundred and sixty-five older adults were selected from the community (n = 92) and nursing home (n = 73) with and without fall history. They were assessed for fall history, functionality, cognitive status, and several gait parameters in SSWS and FWS conditions. RESULTS: Fallers differed from non-fallers in the SSWS, while such differences were not evidenced during the FWS. Cadence and stride width did not differ when living backgrounds were compared. Nursing home residents walked slower than their non-institutionalized peers, regardless of fall history or walking speed. Besides, binary logistic regression analysis showed that living in a nursing home, age, body mass index (BMI), mini-mental state examination (MMSE), and step width were related to falls in the SSWS. On the other hand, living in a nursing home, having a larger BMI and having low MMSE scores were fall predictors in the FWS. CONCLUSION: Fall occurrence can be identified by factors related to living in nursing homes, cognitive status, BMI, and gait parameters, at the SSWS. Cognitive status and BMI are related to falls in the FWS for those living in nursing homes.

Caffeine ingestion increases endurance performance of trained male cyclists when riding against a virtual opponent without altering muscle fatigue.

PURPOSE: Caffeine improves cycling time trial (TT) performance; however, it is unknown whether caffeine is ergogenic when competing against other riders. The aim of this study was to investigate whether caffeine improves performance during a 4-km cycling TT when riding against a virtual opponent, and whether it is associated with increased muscle activation and at the expense of greater end-exercise central and peripheral fatigue. METHODS: Using a randomized, crossover, and double-blind design, eleven well-trained cyclists completed a 4-km cycling TT alone without supplementation (CON), or against a virtual opponent after ingestion of placebo (OP-PLA) or caffeine (5 mg.kg-1, OP-CAF). Central and peripheral fatigue were quantified via the pre- to post-exercise decrease in voluntary activation and potentiated twitch force, respectively. Muscle activation was continually measured during the trial via electromyography activity. RESULTS: Compared to CON, OP-PLA improved 4-km cycling TT performance (P = 0.018), and OP-CAF further improved performance when compared to OP-PLA (P = 0.050). Muscle activation was higher in OP-PLA and OP-CAF than in CON throughout the trial (P = 0.003). The pre- to post-exercise reductions in voluntary activation and potentiated twitch force were, however, similar between experimental conditions (P > 0.05). Compared to CON, OP-PLA increased the rating of perceived exertion during the first 2 km, but caffeine blunted this increase with no difference between the OP-CAF and CON conditions. CONCLUSIONS: Caffeine is ergogenic when riding against a virtual opponent, but this is not due to greater muscle activation or at the expense of greater end-exercise central or peripheral fatigue.

Exploring the Impact of Mental Fatigue and Emotional Suppression on the Performance of High-Intensity Endurance Exercise.

This study investigated the extent to which mental fatigue and emotional suppression affected exercise endurance. Twelve participants performed cycling endurance tests at 80% of their peak power up to the point of exhaustion. Two experimental conditions (mental fatigue [MF] and emotion suppression conditions [ES]) and a control condition (CO) were administered. Participants responded to psychological measures throughout the exercise trials. Both MF and ES conditions hindered exercise performance relative to the CO, and there was no statistically significant difference between the negative effects of both MF and ES conditions. Of note, however, higher levels of subjective fatigue were reported in MF, prior to commencing the exercise test. High cognitive loads that induce MF and/or engaging in ES may reduce high intensity endurance exercise performance among young adults, but further research with greater numbers of participants is needed to replicate and extend these findings.

Gait Parameters of Older Adults according to Their Fall History and Functional Capacity While Walking at Different Speeds.

INTRODUCTION: It is believed that functional capacity and fall history are factors capable of influencing the gait parameters of older adults. Thus, the objective of this study was to verify whether gait parameters of community-dwelling older adults differ according to their functional capacity and fall history when walking at self-selected walking speed (SSWS) and fast walking speed (FWS) using principal component analysis (PCA). METHODS: Two hundred ninety-five participants (82.3% women and 17.7% men) were allocated in four groups according to their fall history and functional capacity: non-fallers with higher functional capacity (NFHFC, n = 94; 69.3 ± 5.5 years), non-fallers with lower functional capacity (NFLFC, n = 114; 72.0 ± 8.1 years), fallers with higher functional capacity (FHFC, n = 29; 70.0 ± 6.0 years), and fallers with lower functional capacity (FLFC, n = 58; 72.5 ± 8.2 years). Fall history, anthropometric data, functional capacity by short physical performance battery and mobility by Timed Up and Go (TUG), and spatiotemporal gait parameters were evaluated. RESULTS: Data analysis indicated that FLFC presented the lowest scores, especially in the Five Times Sit-to-Stand Test and TUG. The PCA showed that the first principal component (PC1) explained the most substantial amount of the data variability in both walking speeds (SSWS and FWS), predominantly including temporal parameters. PC2 composed by spatial outcomes (stride and step length and walking speed) showed the highest effect size. PC1 and PC2 were able to differentiate functional status, regardless of fall history. CONCLUSIONS: Functional capacity showed great importance when analyzing gait parameters at different walking speeds (SSWS and FWS), regardless of fall history. Older adults with high functional capacity demonstrate better performance during gait. Besides, spatiotemporal parameters are the main factors explaining gait variability, both in SSWS and FWS.

Can Age Influence Functional Tests Differently to Predict Falls in Nursing Home and Community-Dwelling Older Adults?

Aim: The aim of this cross-sectional study was to determine which functional tests are able to predict falls in nursing home residents (NHR) and community-dwelling (CDW) older adults grouped by age. Methods: Two hundred and fifty-two older adults were assessed in the following tests, Mini-Mental State Examination, anthropometric characteristics, fall history and functional tests. The participants were assigned to one of the following groups: Young Older Adults (YOA; 60-69 years, n = 102; 27.5% NHR), Old Older Adults (OOA; 70-79 years; n = 100; 23.5% NHR) and Very Older Adults (VOA, ≥80 years; n = 50; 52% NHR). Results: The five times sit-to-stand showed 1.41 odds to experience a fall in the NHR of the VOA. In the CDW, the handgrip strength score decreased the odds to fall occurrence (0.92 odds) in the YOA, while the low score in timed up and go test of the OOA showed 1.21 odds to experience a fall. Conclusions: Therefore, the five times sit-to-stand test can predict falls in NHR of VOA groups, while handgrip strength and timed up and go tests can predict falls in CDW of YOA and OOA groups, respectively.

Muscle function, physical function, and gait in older women with and without knee osteoarthritis

Abstract Aim: To compare muscle function of knee extensors, gait parameters, and physical function in older women with and without knee osteoarthritis (KOA) and to associate these parameters to the KOA incidence in this population. Methods: Sixteen older women with KOA (66.9 ± 5.5 years; 74.9 ± 10.0 kg; 157.9 ± 0.9 cm; 30.2 ± 5.0 kg/m2) and fourteen healthy counterparts (control group: CG; 68.8 ± 5.8 years; 68.9 ± 10.5 kg; 158 ± 0.06 cm; 27.4 ± 4.0 kg/m2) participated in this study. Muscle function, physical function, and gait parameters were evaluated in both groups. The Western Ontario and McMaster Index (WOMAC) questionnaire was answered only by the KOA group. A correlation was performed to verify if KOA incidence was associated with muscle function, physical function, and gait parameters. Results: KOA group showed lower peak torque at 60°/s (30%; p = 0.003) and 180°/s (37%; p < 0.001), greater acceleration time at 60°/s (382%; p < 0.001), lower cadence (12.2%; p = 0.002), slower gait speed (19.5%; p < 0.001) and greater stride time (12.5%; p = 0.001) than CG group. However, there was no difference between groups in physical function (p < 0.0045). The KOA incidence presented a negative correlation with peak torque (rho = −0.602; p < 0.001), cadence (rho = −0.533; p = 0.002), gait speed (rho = −0.633; p < 0.001), stride length (rho = −0.517; p = 0.003) and a positive correlation with stride time (rho = 0.533; p = 0.002) and acceleration time (rho = 0.655; p < 0.001). Conclusion: Our findings suggest that knee osteoarthritis may impair the function of the knee extensors muscles and gait parameters. An association between the ability to produce force rapidly and gait speed with the KOA incidence in older women was also observed.

Multicomponent Exercise Training Improves Gait Ability of Older Women Rather than Strength Training: A Randomized Controlled Trial.

OBJECTIVE: The aim of this study was to compare the effects of multicomponent and strength training programs on dynamic balance, functional capacity, and gait ability in older women. METHODS: Thirty individuals (67 ± 4.3 years; 30.6 ± 3.9 kg/m2) were trained for 12 weeks (3 times per week), following multicomponent (MG: exercises focusing on agility, balance, muscle strength, and aerobic) and strength programs (SG: lower limbs strength exercise). RESULTS: Peak torque of hip flexors (p=0.020) and extensors (p=0.009) and knee flexors (p=0.001) of SG was greater than that of MG at posttraining. In addition, both groups increased peak torque of knee extensors (p=0.002) and plantar extensors with higher effect size for SG (d = -0.41 and -0.48), whereas MG presented higher effect size for plantar flexors muscles (d = -0.55). Only the SG improved the rate of torque development of knee extensors (29%; p=0.002), and this variable was also greater to SG than MG at posttraining (106%). The SG and MG improved dynamic balance although SG presented higher effect size (d = 0.61). Both groups improved the performance on 30 s sit to stand test (p=0.010) with higher effect size for MG (d = -0.54). Only the MG improved the stride length (4%; p=0.011) and gait speed (10%; p=0.024). In addition, the groups improved toe clearance (p=0.035) and heel contact (p=0.010) with higher effect sizes for MG (d = -0.066 and 1.07). CONCLUSION: Strength training should be considered to increase muscle function and dynamic balance in older women, whereas multicomponent training should be considered to increase functional capacity and gait ability in this population.

Is Handgrip Strength a Useful Measure to Evaluate Lower Limb Strength and Functional Performance in Older Women?

AIM: This study aimed to determine the association of handgrip strength with isometric and isokinetic strength (hip, knee and ankle extensor/flexor muscles), and functional capacity in older women. METHODS: The handgrip strength and lower limb strength of 199 older women (60-86 years) were measured using JAMAR and BIODEX dynamometers, respectively. Time Up and Go, Five-times-sit-to-stand and 6m-walk functional tests were evaluated. Pearson correlations were used to determine the relationship between variables. Regression analysis was applied to identify if HS was able to predict TUG performance. The effect of age was analyzed by splitting the participants in a group of older women (OLD; from 60 to 70 years old) and very old women (from 71 to 86 years old). RESULTS: The HS and isometric/isokinetic strength correlations were negligible/low and, in most cases, were non-significant. The correlation between handgrip strength and functional tests also ranged predominantly from negligible (r=0.0 to 0.3) to low (r=0.3 to 0.5), irrespective of the group age. The handgrip strength was not able to explain the variance of the TUG performance. CONCLUSION: Generalizing handgrip strength as a practical and straightforward measure to determine lower limbs and overall strength, and functional capacity in older women must be viewed with caution. Handgrip strength and standard strength measures of the lower limbs and functional tests present a negligible/low correlation.

Caffeine increases peripheral fatigue in low- but not in high-performing cyclists.

The influence of cyclists' performance levels on caffeine-induced increases in neuromuscular fatigue after a 4-km cycling time trial (TT) was investigated. Nineteen cyclists performed a 4-km cycling TT 1 h after ingesting caffeine (5 mg·kg-1) or placebo (cellulose). Changes from baseline to after exercise in voluntary activation (VA) and potentiated 1 Hz force twitch (Qtw,pot) were used as markers of central and peripheral fatigue, respectively. Participants were classified as "high performing" (HP, n = 8) or "low performing" (LP, n = 8) in accordance with their performance in a placebo trial. Compared with placebo, caffeine increased the power, anaerobic mechanical power, and anaerobic work, reducing the time to complete the trial in both groups (p < 0.05). There was a group versus supplement and a group versus supplement versus trial interaction for Qtw,pot, in which the postexercise reduction was greater after caffeine compared with placebo in the LP group (Qtw,pot = -34% ± 17% vs. -21% ± 11%, p = 0.02) but not in the HP group (Qtw,pot = -22% ± 8% vs. -23% ± 10%, p = 0.64). There was no effect of caffeine on VA, but there was a group versus trial interaction with lower postexercise values in the LP group than in the HP group (p = 0.03). Caffeine-induced improvement in 4-km cycling TT performance seems to come at the expense of greater locomotor muscle fatigue in LP but not in HP cyclists. Novelty Caffeine improves exercise performance at the expense of a greater end-exercise peripheral fatigue in low-performing athletes. Caffeine-induced improvement in exercise performance does not affect end-exercise peripheral fatigue in high-performing athletes. High-performing athletes seem to have augmented tolerance to central fatigue during a high-intensity time trial.

The Effects of Different Exergame Intensity Training on Walking Speed in Older Women.

Objective: It is not known if the intensity in which exergames are performed can change gait parameters at different walking speeds. This study was designed to determine if a training program based on exergame exercises performed at different intensities (moderate vs. vigorous) influences walking speed and gait parameters in older adult women. Methods: After applying the inclusion criteria, 20 participants (69.5 ± 5.4 years) were randomized into two groups: moderate (11-13 perceived exertion) and vigorous (14-16 perceived exertion). Walking speed and gait parameters at self-selected walking speed (SSWS) and maximal walking speed (MWS) were evaluated before and after 3 months of exergame training. The walking speed and gait parameters were measured with an instrumented walkway. The walking speed reserve (WSR) was calculated as a difference and ratio. Results: There was pre-to-post effect of walking speed at self-selected walking pace (pre = 112.1 ± 16.4 cm.s-1; post = 124.8 ± 16.4 cm.s-1), in WSR calculated as ratio (pre = 1.35 ± 0.08; post = 1.28 ± 0.09), in a number of gait parameters at SSWS (step length, stride length, stride velocity, step time, stride time, swing time, stance time, single support, double support, gait cycle time, and cadence) and at MWS (step time, stride time, swing time, single support, double support, gait cycle time, and cadence). Conclusion: Irrespective of the exercise intensity, exergame training improved walking speed only at a self-selected walking pace and some gait parameters at self-selected and MWS in older women.

Postural Control of People in treatment for substance use disorder

Abstract Aims: One of the common sequelae of chronic abuse of alcohol and/or illicit drugs is the impairment of body balance control, caused by long-term neurological damage. This study aimed to investigate the postural control of individuals hospitalized for the treatment of substance use disorder (initial phase) and to compare the results obtained by a control group. Method: For this, One-hundred fourteen individuals hospitalized for the treatment of substance use disorder and eighty-eight healthy controls, all males, were analyzed. Body mass, height, and waist circumference were measured. Were performed a balance test in a static upright position with feet side by side using a plantar pressure platform. Results: Individuals with substance use disorder have shown significantly lower results on body balance compared with controls. Individuals with chemical dependence showed balance results open-eyes, similar/lower than control subjects with close-eyes. Still, those who used only alcohol or alcohol combined with other illicit drugs presented worse results. Finally, impairments in body balance variables showed a significant correlation with age and substance time of use. Conclusion: Even in the early stage of treatment, substance use disorder considerably impairs the balance of the investigated men. The worst results were found in alcohol-dependents (alcohol alone or alcohol combined with other drugs).

Multicomponent Training Program with High-Speed Movement Execution of Ankle Muscles Reduces Risk of Falls in Older Adults.

The purpose of this study was to investigate the effects of multicomponent training program, designed to improve the torque around the ankle joint performing high-speed movement execution, on healthy older adults. Participants were balanced by torque around the ankle joint and randomly allocated to either exercise (n = 12, 69.7 ± 4.8 years, 74.6 ± 16.8 kg, 1.63 ± 0.10 m) or control group (CG) (n = 14, 70.86 ± 6.48 years; 73.5 ± 13.4 kg, 1.56 ± 0.05 m). The exercise group (EG) performed a multicomponent training of resistance, agility, and coordination exercises, focusing on the plantar flexor muscles during 12 weeks (3 days per week). Outcome measures were torque (plantar flexion and extension), reactive capacity (Step test), and functional mobility (gait and timed up and go [TUG] test). The training program was induced to increase peak torque of extensor muscles around the ankle joint to EG (Δ = 50%; d = 1.59) compared to the CG. Such improvement was converted to reactive capacity improvements considering the decrease in the execution time of the Swing phase and in the Total time of the Step test (Δ = 19%; d = 0.93, Δ = 14%; d = 1.02, respectively). Gains in functional mobility were verified by the increase of the walking speed (Δ = 15%; d = 1.37) and by the smaller time of execution of TUG test (Δ = 17%; d = 1.73) in the EG. Therefore, the multicomponent training was effective to reduce or to reverse muscular age-related declines, which are associated with functional capacity and reduction of fall risk in older adults.

Validity, Reliability, and Diagnostic Accuracy of Ratings of Perceived Exertion to Identify Dependence in Performing Self-care Activities in Older Women.

BACKGROUND: Dependence in self-care activities among older women has been previously evaluated through performance-based tests. However, these tests have presented inability to accurately distinguish between dependent and independent older adults in performing activities of daily living. AIM: To examine the validity, reliability, and diagnostic accuracy of rating of perceived exertion (RPE) to identify dependence in performing self-care activities in older women. METHODS: Thirty-five older women performed two different constant-load tasks (walking on treadmill at 4 km/h for five minutes and arm curls with two kg for one minute), reporting RPE at the end, in four sessions. Performance-based tests (30-second chair stand and 6-minute walk) were also evaluated. Katz Index and Lawton and Brody questionnaires were applied to evaluate the dependence level in performing basic and instrumental activities of daily living. RESULTS: RPE was greater on the first session (RPE 14 ± 2) than second session (RPE 13 ± 2), while it was similar through other sessions, with high values of intraclass coefficient correlation (0.96-0.99). Basic activities of daily living and instrumental activities of daily living presented high correlations with RPE measures (0.75-0.82), whereas performance-based tests presented moderate correlations (0.47-0.59). RPE responses explained the most variance in identifying dependence in self-care activities and presented high diagnostic accuracy to differentiate dependent from independent older women. So the hypotheses had been confirmed that RPE responses in constant-load exercise are better predictors of dependence in self-care activities than performance-based tests. CONCLUSIONS: RPE of constant-load physical tasks was valid, reliable, and accurate in identifying dependence in performing self-care activities in older women; therefore, it is possible to use the perceived exertion to identify dependence in performing activities of daily living in older women.

Does functional capacity, fall risk awareness and physical activity level predict falls in older adults in different age groups?

The aims of this study were to examine whether: i) functional capacity and physical activity level differ between fallers and non-fallers older adults, by controlling for fall risk awareness; ii) functional capacity, fall risk awareness and physical activity differ between fallers and non-fallers older adults, by controlling for age; iii) variables and which may predict falls in different age groups. 1826 older adults performed a series of functional tests and reported their fall episodes, fall risk awareness and physical activity level. The overall incidence of falls was high (40.2%), and falls risk awareness scores reduced with age. The older adults with greater falls risk awareness and non-fallers presented better scores in all functional tests and physical activity level (P < .05). Functional tests and falls risk awareness differed among age groups and differed between fallers and non-fallers, irrespective of age group (P < .05). Falls risk awareness predicted falls in all age groups (odds ranging: 1.05-1.09). Handgrip strength and balance scores predicted falls until 79 years (OR = 1.04, 95%CI = 1.01-1.06). The physical activity level predicted falls up to 70 years (OR = 1.09, 95%CI = 1.06-1.12). Functional mobility was able to predict falls up to 80 years (OR = 1.06, 95%CI = 1.01-1.08). Therefore, according to age, functional capacity, physical activity level and falls risk awareness can be a predictor of falls in older adults.

Effects of additional external load manipulation on perceptual and physiological responses during exergame

This study tested whether performing exergames with and without additional external load could induce to different internal load demand for young adults. Methods: Fifteen young women (24.4 ± 4.06 years) participated in the study. Electromyography (EMG) activity, heart rate (HR) and overall and local rating of perceived exertion (RPE) were determined in "Just Dance" and "Ski" exergames without additional external load and with additional external load of 5% of body mass attached bilaterally to the ankles in "Just Dance" and using a weight vest in "Ski". Results: EMG, HR and overall RPE presented similar responses between loads in both exergames (p>.05). However, local RPE differentiate internal load only in "Just Dance", with higher values with additional load (with additional load: 11.2 ± 2.1 RPE; without additional load: 10.3 ± 1.4 RPE; p = .037). Conclusion: Therefore, performing exergames with an additional external load of 5% of young women body mass did not induce different internal load demand in "Just Dance" and "Ski" exergames compared to performing such games without external load. However, the greater local RPE in "Just Dance" exergame after adding the external load suggests that a higher amount of load (i.e., > 5% of body mass) to this population may generate different internal load demand.(AU)

Variability and reliability of gait kinematic parameters after controlled tripping in older adults: a preliminary study / Variabilidade e confiabilidade dos parâmetros cinemáticos da marcha de idosos após um tropeço controlado: estudo preliminar

ABSTRACT Approximately 21% of the falls in older adults occur due to tripping, while walking. There is a paucity of information regarding the gait variability and reliability when a tripping is induced in different days mainly with elderly. It was aimed to analyze the variability and the reliability (intra- and inter-day) of spatiotemporal gait parameters and joint angles after controlled tripping in older adults. Eight healthy older women participated. The trip was induced during the early-mid swing phase on the transposing segment and the kinematic data was obtained from trials. The variability and reliability of spatiotemporal gait parameters and joint angles during the gait cycle were checked through the coefficient of variation (CV), the intraclass coefficient correlation (ICC) and the standard error of measurement (SEM). The variability of spatiotemporal and intra- and inter-day angular parameters was low for most variables, except for plantar flexion. The SEM was low for all parameters. Intra-day reliability was moderate to high for the spatiotemporal and angular parameters. Inter-day reliability was considered low to moderate for all parameters. The variables did not differ between instants and days. Experimental procedures demonstrate that the walking pattern did not change, but should be considered with caution in studies that include intervention, particularly for angular parameters during gait.

RESUMO Aproximadamente 21% das quedas em idosos ocorrem como consequência de tropeços ao caminhar. Há uma escassez de informações referentes à variabilidade e à confiabilidade dos parâmetros cinemáticos da marcha em diferentes dias de avaliação, sobretudo com idosos. Buscou-se analisar a variabilidade e a confiabilidade (intra e inter-dia) dos parâmetros espaço-temporais e angulares da marcha de idosos, após a indução de tropeço controlado. Oito idosas participaram do estudo. O tropeço foi induzido durante o início da fase de balanço da marcha. Foram analisados os dados cinemáticos das tentativas de marcha. A variabilidade e confiabilidade dos parâmetros espaço-temporais da marcha foram verificados através do coeficiente de variação (CV), do coeficiente de correlação intraclasse (ICC) e do erro padrão de medida (SEM). A variabilidade dos parâmetros espaço-temporais e angulares intra e inter-dia foi baixa para a maioria das variáveis, à exceção da flexão plantar. O SEM foi baixo para todos os parâmetros. A confiabilidade intra-dia foi moderada a alta para os parâmetros espaço-temporais e angulares; A confiabilidade inter-dia foi baixa a moderada para todos os parâmetros. As variáveis não diferiram entre instantes e dias. Apesar do padrão de marcha não ter alterado deve ser analisado com cautela em estudos que incluam intervenção, particularmente para os parâmetros angulares.

Front Crawl Swimming Performance and Bi-Lateral Force Asymmetry during Land-Based and Tethered Swimming Tests.

The aims of this study were to investigate whether land-based and tethered swimming strength tests can explain swimming performance in 200-meter front crawl and, whether these tests were able to identify bilateral symmetry in force production. In the first session, eighteen swimmers completed a maximum effort 200 m front crawl swim (swimming performance) and 15 seconds maximal effort tethered front crawl swim. In the second session, participants performed the upper extremity isometric strength test. Peak force production of tethered swimming and isometric strength tests were significantly correlated for the strongest and weakest sides (r = 0.58 and r = 0.63, respectively; p < 0.05), but only peak force production during tethered swimming correlated with 200 m swimming performance time (r = -0.55, p < 0.05). Bilateral asymmetries in peak force and rate of force development were similar between the tethered swimming and isometric strength tests (peak force: 13%, p = 0.24; rate of force development: 15%, p = 0.88) However, both tests detected significant difference of peak force and rate of force development between body sides. The tethered swimming test can partially explain the 200 m front crawl swimming performance. In addition, the land-based and tethered swimming tests may be used to identify bilateral asymmetry of swimming.