Influence of a brisk walking program on postural responses in sedentary older women: a randomised trial.

This study analyzes the evolution in kinematic and non-linear stabilometric parameters in elderly sedentary women selected to participate in a brisk walking program. Ninety-four women were randomly selected for a program of 78 sessions over 6 months, with three sessions of 60 min per week. On the force platform, participants were assessed with both eyes opened as well as eyes closed during a period of 51.2 s and the sampling frequency was 40 Hz. The main dependent kinematic variables were the length, stabilogram surface, and the mean position in anteroposterior as well as medio-lateral directions. For the dynamic approach, we have selected the parameters of recurrence quantification analysis, sample entropy, and multiscale entropy. The kinematic and the time series analysis of group × time interactions demonstrated that 6 months of walk-training lacked influence on kinematic postural responses and on dynamical measurements. The weekly brisk walking program was situated on flat ground and consisted of three 60-min weekly sessions lasting 6 months, leading to no significant effect on postural responses. In regards to international recommendations brisk walking is a pertinent exercise. However, in older sedentary women, our study indicated a systemic lack of influence of 6 months' walk-training on flat ground on kinematic postural responses and on dynamical measures obtained by time series analysis.

Influence of a brisk walking program on isokinetic muscular capacities of knee in sedentary older women.

This study analyzed the evolution in peak torque (PT) and mean power (MP) isokinetic parameters in the quadriceps and hamstring muscles of elderly sedentary women who were randomly selected to participate in a brisk walking program for 6 months. The 121 sedentary women of this study presented a mean score of 5.3 (±1.7) on the Physical Activity Questionnaire for the Elderly and covered 86 % of the theoretical distance on the 6-min walk test. The isokinetic evaluation was performed on both sides at 60°/s and 180°/s. PT and MP were selected for analysis. Women in the trained group (n = 61) participated in a program of 78 sessions over 6 months with three sets of 60 min of exercise per week. For this group, heart rate, time and distance were, respectively, 125.2 bt/min (±10), 37.9 min (±4.2) and 3756.3 m (±445.4). The analysis of the group × time interaction demonstrated an increase in the PT of the dominant-side hamstrings (p < 0.001). In the trained group, we observed a significant increase in PT at 60°/s for the hamstrings on both sides (0.01 < p < 0.02) and a significant increase in MP for the hamstrings at 60°/s on the nondominant side (p < 0.05). The study indicates a minor, though significant, influence of a brisk walking program on the peak torque and mean power of the quadriceps and hamstring muscles in sedentary women over 60 years.

Physical function decline and degradation of postural sway dynamics in asymptomatic sedentary postmenopausal women.

BACKGROUND: Postural control is an important aspect of physical functioning. OBJECTIVE: To determine whether postural sway complexity could discriminate asymptomatic sedentary postmenopausal women with normal or subnormal physical function from those with lower physical function. DESIGN: Cross-sectional study. SETTING: Department of Geriatrics, University Hospital of Montpellier. PARTICIPANTS: 126 community-dwelling women aged 55 to 76 recruited though public meetings aimed at promoting physical activity in postmenopausal women. MEASUREMENTS: Women were asked to stand still on a force platform, either with eyes open (EO) or eyes closed (EC). Physical function was estimated using the Six-Minute Walking Distance (6MWD) test, expressed as a percentage of the predicted 6MWD (%-pred 6MWD) based on age, gender, body height, and weight. In addition to traditional stabilometric measures, dynamical measures (percentage of determinism of recurrence quantification analysis [DETRQA], sample entropy [SampEn] and complexity index of multiscale entropy [CIMSE]) were used to quantify the complexity of center of pressure (COP) time series (DETRQA: predictability, SampEn: regularity, CIMSE: multiscale regularity). RESULTS: None of the traditional stabilometric measures differentiated women with lower (%-pred 6MWD ≤ 85.5%) from those with subnormal or normal (%-pred 6MWD > 85.5%) physical function. Conversely, women with lower physical function showed lower SampEn values in the AP direction in both EO and EC conditions, as well as lower SampEn and higher DETRQA values in the ML direction in EC condition. No significant difference in the CIMSE values was found between the two groups. CONCLUSION: Lower physical function was found to be associated with lower postural sway complexity (higher regularity and predictability) in asymptomatic sedentary postmenopausal women, especially in the absence of vision. Future work is needed to determine whether a decrease in postural sway complexity could predict future decline in physical function in these women.

Effects of a six-month walking intervention on depression in inactive post-menopausal women: a randomized controlled trial.

OBJECTIVES: Physical inactivity and advanced age are associated with risk of depressive disorders. Physical activity can reduce depressive symptoms in older subjects with depressive disorders. We investigated whether a walking intervention program may decrease the occurrence of depressive symptoms in inactive post-menopausal women without depression. METHOD: A total of 121 participants aged 57-75 years were randomly assigned to a six-month moderate intensity walking intervention (three times a week, 40 minutes per session, supervised and home-based) or to a control group (waiting list). Inactivity was assessed using the Physical Activity Questionnaire for the Elderly. Depression levels were measured pre- and post-intervention with the Beck depression inventory (BDI). Several baseline measures were considered as possible predictors of post-intervention BDI score. RESULTS: Participants in the walking intervention showed a significant decrease in depression as compared with controls. Baseline cognitive-BDI subscore, subjective health status, body mass index and adherence were post-intervention BDI score predictors. CONCLUSION: A six-month, three-session per week, moderate intensity walking intervention with a minimal 50% adherence rate reduces depression in post-menopausal women at risk for depression due to physical inactivity. This type of walking intervention could be considered as a widely accessible prevention strategy to prevent depressive symptoms in post-menopausal women at risk of depression.