ABSTRACT
Cancer is the leading cause of death among Latinos in the U.S. While engaging in a physically active lifestyle
is one of the most important modifiable behaviors for reducing cancer risk; few Latinas achieve health-
enhancing levels of physical activity (PA) recommended by the National PA Guidelines, particularly for muscle-
strengthening activities (MSA). For instance, 44% of Latinas meet the national guidelines for aerobic PA but
only 17% meet the full guidelines for both aerobic and MSA. While the benefits of aerobic MVPA are well
established for cancer and chronic disease prevention, participating in regular MSA may be key to further
reducing cancer risk, as adherence to MSA guidelines has been associated with a 19% to 31% lower cancer
mortality risk, independent of aerobic PA. There is a need for interventions promoting MSA in Latinas.
However, only a select few MSA interventions have included Latinas in their sample, and none to our
knowledge, were designed exclusively for this group or addressed socio-cultural factors influencing Latinas'
muscle-strengthening behaviors (e.g., perception that MSA is for men; MSA is an avoided topic in their culture
and social circles; belief that women should only do certain types of MSA). Moreover, existing interventions
often involved in-person exercise programs, which can be inaccessible to many Latinas due to barriers such as
lack of transportation or fear of immigration enforcement. Our research team has previously developed and
tested aerobic moderate-to-vigorous PA (MVPA) interventions for Latinas that overcome barriers to in-person
programs and address PA-related socio-cultural factors. These theory-driven, individually tailored interventions
have shown success at increasing aerobic MVPA among Latina women in both print and Internet-based
randomized controlled trials. Thus, our web-based intervention (Pasos Hacia la Salud), in particular, provides
an ideal platform for promoting muscle-strengthening PA in this at-risk population. To address the gap in
literature on muscle-strengthening PA, we recently conducted qualitative interviews with 19 Latinas to identify
theory-based barriers and facilitators of muscle-strengthening PA, then developed MSA intervention materials
and are further refining for cultural appropriateness, relevance, and appeal in Latinas. In the proposed
research, we will incorporate the newly developed MSA promotion materials into our existing Pasos Hacia la
Salud (Pasos) web-based aerobic MVPA intervention and conduct a 12-week fully online randomized pilot trial
testing the preliminary efficacy of the newly adapted web-based aerobic plus MSA intervention for Latinas. Fifty
Latina adults (i.e., aged 18-65 years) will be randomized to either the: 1) original Pasos aerobic MVPA
intervention arm, or 2) a Pasos aerobic MVPA plus MSA intervention arm. Our study aims to 1) Assess the
preliminary efficacy of the aerobic and muscle-strengthening intervention for increasing MSA, and 2) Explore
potential mediators and moderators of MSA. This interactive and highly disseminable approach can achieve
significant health improvements in an at-risk population.