Responsiveness of Physical Activity Measures Following Exercise Programs after Total Knee Arthroplasty

Objectively Measured Physical Activity, Sedentary Behavior and Functional Performance before and after Lower Limb Joint Arthroplasty: A Systematic Review with Meta-Analysis

Patients after joint arthroplasty tend to be less physically active; however, studies measuring objective physical activity (PA) and sedentary behavior (SB) in these patients provide conflicting results. The aim of this meta-analysis was to assess objectively measured PA, SB and performance at periods up to and greater than 12 months after lower limb arthroplasty. Two electronic databases (PubMed and Medline) were searched to identify prospective and cross-sectional studies from 1 January 2000 to 31 December 2020. Studies including objectively measured SB, PA or specific performance tests in patients with knee or hip arthroplasty, were included in the analyses both pre- and post-operatively. The risk of bias was assessed using the Scottish Intercollegiate Guidelines Network (SIGN). After identification and exclusion, 35 studies were included. The data were analyzed using the inverse variance method with the random effects model and expressed as standardized mean difference and corresponding 95% confidence intervals. In total, we assessed 1943 subjects with a mean age of 64.9 (±5.85). Less than 3 months post-operative, studies showed no differences in PA, SB and performance. At 3 months post-operation, there was a significant increase in the 6 min walk test (6MWT) (SMD 0.65; CI: 0.48, 0.82). After 6 months, changes in moderate to vigorous physical activity (MVPA) (SMD 0.33; CI: 0.20, 0.46) and the number of steps (SMD 0.45; CI: 0.34, 0.54) with a large decrease in the timed-up-and-go test (SMD −0.61; CI: −0.94, −0.28) and increase in the 6MWT (SMD 0.62; CI: 0.26–0.98) were observed. Finally, a large increase in MVPA (SMD 0.70; CI: 0.53–0.87) and a moderate increase in step count (SMD 0.52; CI: 0.36, 0.69) were observed after 12 months. The comparison between patients and healthy individuals pre-operatively showed a very large difference in the number of steps (SMD −1.02; CI: −1.42, −0.62), but not at 12 months (SMD −0.75; −1.89, 0.38). Three to six months after knee or hip arthroplasty, functional performance already exceeded pre-operative levels, yet PA levels from this time period remained the same. Although PA and functional performance seemed to fully restore and exceed the pre-operation levels at six to nine months, SB did not. Moreover, PA remained lower compared to healthy individuals even longer than twelve months post-operation. Novel rehabilitation protocols and studies should focus on the effects of long-term behavioral changes (increasing PA and reducing SB) as soon as functional performance is restored.

Responsiveness of Device-Based and Self-Report Measures of Physical Activity to Detect Behavior Change in Men Taking Part in the Football Fans in Training (FFIT) Program

The capacity of physical activity (PA) measures to detect changes in PA within interventions is crucial. This is the first study to examine the responsiveness of activPAL3™ and the International Physical Activity Questionnaire (IPAQ; Short Form) in detecting PA change during a 12-week group-based, men-only weight management program-Football Fans in Training (FFIT). Participants wore an activPAL3™ and completed the IPAQ pre- and post-program (n = 30). Relationships between change scores were assessed by Spearman's correlations. Mean or median changes in PA were measured using paired samples t-tests and Wilcoxon signed-rank tests. Responsiveness to change was assessed utilizing Standardized Response Mean (SRM). Both device-based and self-report measures demonstrated significant changes pre-post intervention, although these changes were not significantly correlated. The SRM values for changes in activPAL3™ metrics were: 0.54 (MET-mins/day); 0.53 (step counts/day); and 0.44 (MVPA/day), indicating a small to medium responsiveness to change. SRM values for changes in IPAQ scores were: 0.59 (for total PA mins/day); 0.54 (for total MET-mins/day); 0.59 (for walking MET-mins/day); 0.38 (for vigorous MET-mins/day); and 0.38 (for moderate MET-mins/day), revealing a small to medium responsiveness to change. These findings reveal that two commonly used device-based and self-report measures demonstrated responsiveness to changes in PA. While inclusion of both device-based and self-report measures is desirable within interventions it is not always feasible. The results from this study support that self-reported measures can detect PA change within behavioral interventions, although may have a tendency to overestimate changes compared with device-based measures on absolute values, but not standardized response values.