A Mobile Health Team Challenge to Promote Stepping and Stair Climbing Activities: Exploratory Feasibility Study.

BACKGROUND: Mobile health (mHealth) approaches are growing in popularity as a means of addressing low levels of physical activity (PA). OBJECTIVE: This study aimed to determine the validity of wearables in measuring step count and floor count per day and assess the feasibility and effects of a 6-week team challenge intervention delivered through smartphone apps. METHODS: Staff and students from a public university were recruited between 2015 and 2016. In phase 1, everyone wore a Fitbit tracker (Charge or Charge HR) and an ActiGraph for 7 days to compare daily step count estimated by the two devices under free-living conditions. They were also asked to climb 4 bouts of floors in an indoor stairwell to measure floor count which was compared against direct observation. In phase 2, participants were allocated to either a control or intervention group and received a Fitbit tracker synced to the Fitbit app. Furthermore, the intervention group participants were randomized to 4 teams and competed in 6 weekly (Monday to Friday) real-time challenges. A valid day was defined as having 1500 steps or more per day. The outcomes were as follows: (1) adherence to wearing the Fitbit (ie, number of days in which all participants in each group were classified as valid users aggregated across the entire study period), (2) mean proportion of valid participants over the study period, and (3) the effects of the intervention on step count and floor count determined using multiple linear regression models and generalized estimating equations (GEEs) for longitudinal data analysis. RESULTS: In phase 1, 32 of 40 eligible participants provided valid step count data, whereas all 40 participants provided valid floor count data. The Fitbit trackers demonstrated high correlations (step count: Spearman ρ=0.89; P<.001; floor count: Spearman ρ=0.98; P<.001). The trackers overestimated step count (median absolute error: 17%) but accurately estimated floor count. In phase 2, 20 participants each were allocated to an intervention or control group. Overall, 24 participants provided complete covariates and valid PA data for analyses. Multiple linear regressions revealed that the average daily steps was 15.9% higher for the intervention group (95% CI -8.9 to 47.6; P=.21) during the final two intervention weeks; the average daily floors climbed was 39.4% higher (95% CI 2.4 to 89.7; P=.04). GEE results indicated no significant interaction effects between groups and the intervention week for weekly step count, whereas a significant effect (P<.001) was observed for weekly floor count. CONCLUSIONS: The consumer wearables used in this study provided acceptable validity in estimating stepping and stair climbing activities, and the mHealth-based team challenge interventions were feasible. Compared with the control group, the participants in the intervention group climbed more stairs, so this can be introduced as an additional PA promotion target in the context of mHealth strategies. Methodologically rigorous studies are warranted to further strengthen this study's findings.

Physostigmine reverses cognitive dysfunction caused by moderate hypoxia in adult mice.

BACKGROUND: Cognitive changes associated with moderate hypoxia in rodents may result from the diminished functioning of central cholinergic neurotransmission. We designed this study to examine whether treatment with physostigmine (PHY), an acetylcholinesterase inhibitor, could improve the impairment of working memory after hypoxic hypoxia. METHODS: We randomized 90 Swiss Webster, 30-35 g mice (6-8 wks) to three hypoxia groups at fraction of inspired oxygen, FiO2 = 0.10 (1. no treatment; 2. PHY 0.1 mg/kg intraperitoneally administered immediately before; or 3. after hypoxia), or to two room air groups (given either no treatment or PHY after an insult). An object recognition test was used to assess short-term memory function. The object recognition test exploits the tendency of mice to prefer exploring novel objects in an environment when a familiar object is also present. During the 15 min training trial, two identical objects were placed in two defined sites of the box. During the test trial performed 1 h later, one of the objects was replaced by a new object with a different shape. The time spent exploring the two objects was automatically recorded by a video camera and associated software. The performance was analyzed with ANOVA, followed by post hoc comparisons using the Newman-Keuls test when appropriate. P values <0.05 were considered significant. RESULTS: Untreated mice subjected to hypoxia at Fio2 = 0.1 spent significantly less time exploring a novel object on testing day 1 than did untreated mice breathing room air. Performance of the mice subjected to hypoxia, who received physostigmine after, but not before, the insult did not differ from the control group. CONCLUSION: Moderate hypoxia impairs rodents' performance in a working memory task. It appears that changes are transient, because the cognitive functioning of the mice returned to the baseline level 7 days after treatment. Postinsult administration of PHY prevented deterioration of cognitive function. An increased level of acetylcholine in the central nervous system may be responsible for the improved performance of the hypoxia-treated mice.