Get Fit with MA? Estimating the Impact of Medicare Advantage on Physical Activity

• In Event: Policies to Incentivize Engagement in Healthy Behaviors

Abstract

This study investigates whether enrollment in Medicare Advantage (MA) induces physical activity among older adults, relative to those covered under Traditional Medicare (TM). Using nationally representative survey data from 2012 to 2022, we use a fuzzy regression discontinuity design centered at the age-65 Medicare eligibility threshold. To solve the selection bias and isolate the effect of MA on the individuals whose insurance choices are shaped by this policy cutoff, we restrict the sample to adults who turned 65 during the study period and who were already physically active prior to becoming Medicare-eligible. We also exclude respondents who enrolled in MA before age 65 to ensure valid identification.

Our main empirical strategy uses an age 65 or older as an instrument for MA enrollment and estimates the local average treatment effect (LATE) on weekly physical activity frequency. We find that MA enrollment leads to approximately 2.7 days increase in vigorous physical activity per week compared to TM enrollment. This result is consistent with wellness features commonly covered in MA plans, such as free access to fitness programs and gym membership.

Further, we use doubly robust estimator which adjusts for observed differences using inverse probability weighting for robustness check. The results remain consistent in direction, strengthening the credibility of our main findings.

For policy implication, this study provides new evidence that the structure of public insurance programs can influence individual health behavior especially among seniors. In particular, Medicare Advantage’s wellness and fitness coverage induces more active lifestyles, offering insights for policymakers aiming to promote healthy aging through targeted benefit structures.

Author

• Jong Min (Jason) Jung, University of Washington
  Presenting Author