Black women are F.I.R.E.- Fitting in resistance exercise: A culturally tailored and theory-based exercise intervention for young adult women

Abstract

BACKGROUND: Black women have the lowest rates of physical activity (PA) in the United States coupled with high prevalence of cardiometabolic risk factors. Resistance exercise (RE) has been shown to mitigate these health risks, however its effects and feasibility to increase exercise adherence in young Black women has been understudied. Concepts from the Social Cognitive Theory (SCT) and the Self-Determination Theory (SDT) have been associated with exercise adherence, but have not been used in conjunction with culturally-tailored strategies in this population to improve exercise adherence, physical and psychological outcomes. PURPOSE: This study examined the effects of a culturally tailored and theory-based RE intervention on adherence to RE, cardiometabolic disease risk factors, body composition, strength, behavioral aspects from the SCT (self-regulatory strategies and self-efficacy) and SDT concepts (competence, autonomy, relatedness, source of self-regulation) in young Black women over 24 weeks between a motivational exercise group (MEG) and a standard exercise group (SEG). METHODS: Thirty young, inactive Black women were randomized into MEG or SEG and received in-person RE training from a Black woman trainer in a fitness center in a predominantly Black neighborhood. Women in MEG discussed weekly topics about self-regulation and barriers and motivators for exercise in Black women while also working on improving competence and autonomy for RE. These discussions were followed up with text messages twice per week. Women in SEG only received one-on-one training. Cardiometabolic risk factors [total cholesterol, triglycerides, high-density lipoproteins (HDL), low-density lipoprotein (LDL), glucose, and waist circumference], body composition, and muscular strength were measured. Psychological outcomes included self-regulation, the basic psychological needs (competence, autonomy, relatedness), sources of motivation (amotivation, external, introjected, identified, integrated, and intrinsic motivation), and self-efficacy. All outcomes were assessed at pre-test, post-test, and a 3-month follow-up. RE adherence was measured for supervised and unsupervised RE sessions. RESULTS: Women in MEG (n = 14, mean age: 23.29±3.77 years) completed 93.9% of supervised sessions compared to 88.8% in SEG (n = 13, mean age: 26.15±3.29 years), and 14.3% completed at least 2 or more days of RE unsupervised versus 15.4% in SEG. Mixed ANOVAs showed no group by time interactions for physical or psychological outcomes, but there was a main effect of time. Bonferroni post-hoc analyses showed women in MEG significantly increased lean body mass (p < .001), decreased body fat percentage (p = .005), increased upper (p = .002) and lower body strength (p < .001) from pre-test to post-test, and upper and lower body muscular strength remained significantly higher than baseline at 3-month follow up (p < .001). Women in SEG exhibited increases in lean body mass at post-test (p = .023), upper body strength at 3-month follow-up (p < .001), and lower body strength at post-test and 3-month follow-up (p < .001). Bonferroni post-hoc analyses following the main effect of time revealed that women in both groups experienced increases in autonomy and competence at post-test (p < .001), but ultimately decreased from post-test to 3-month follow-up (MEG: p = .008, p < .001; SEG: p = .003, p = .002). Relatedness increased significantly for MEG (p = .001) and SEG (p < .001) from pre- to post-test, but showed a decrease from post-test to 3-month follow-up for MEG (p = .025). Significant increases in MEG and SEG occurred for identified regulation (p < .001; p = .004), integrated regulation (p < .001; p = .027), and intrinsic motivation (p < .001; p < .001) from pre- to post-test visits. For MEG, values were significantly higher at 3-month follow-up in comparison to pre-test for identified regulation (p < .001), integrated regulation (p = .002), and intrinsic motivation (p < .001). For SEG, only intrinsic motivation remained higher at 3-month follow-up in comparison to pre-test values (p = .034). Introjected regulation continually increased over the three timepoints for MEG (pre-test to 3-month follow-up: p = .003; post-test to 3-month follow-up: p = .006). Self-efficacy increased for MEG test (p < .001) and SEG (p = .014) from pre- to post-test, and decreased in MEG from post-test to 3-month follow-up (p = .011). Self-regulation increased in both groups at post-test (p < .001), and remained significantly higher at 3-month follow-up from baseline for MEG (p = .002) and SEG (p = .017). CONCLUSION: Ten weeks of surface level culturally-tailored RE can improve lean body mass, body fat percentage, and muscular strength in Black women. Additionally, those who successfully participated in more than 1 day of RE during the unsupervised period of the study increased basic psychological needs, and forms of autonomous and intrinsic motivation 12 weeks beyond in-person training. Deeper level cultural tailoring failed to significantly improve adherence. However, better methods are needed to improve adherence to RE during unsupervised training periods for young Black women.