People with memberships to health clubs had increased aerobic and resistance physical activity levels and favorable cardiovascular health outcomes compared with non-members, according to a cross-sectional study.

Lead researcher Elizabeth C. Schroeder, MS, of the University of Illinois at Chicago, and colleagues published their results online in PLoS One on Jan. 20.

The study examined 204 health club members and 201 non-members for five months in 2013. All of the participants were 30 to 64 years old, and lived in Ames, Iowa. They also were not on blood pressure medications, were not currently pregnant and did not have a history of MI, stroke or cancer.

The researchers recruited participants through flyers, email, word of mouth and in-person at Iowa State University and four health clubs. Most of the participants were college faculty and staff members, and 85 percent were white.

The participants completed an evaluation that included resting blood pressure, resting heart rate, waist circumference, weight and height. They also filled out a questionnaire that asked about their physical activity and medical history.

The study found that 87 percent of health club members and 30 percent of non-members met the aerobic physical activity guidelines that HHS established. The guidelines recommend at least 150 minutes of moderate-intensity or 75 minutes of vigorous-intensity aerobic activity per week or an equivalent combination of both.

Meanwhile, 84 percent of health club members and 36 percent of non-members met HHS’s resistance physical activity guidelines. The guidelines recommend participation in muscle-strengthening activities on two or more days per week.

Further, 75 percent of health club members and 18 percent of non-members met both the aerobic and resistance physical activity guidelines.

After adjusting for age, sex and body mass index, the odds ratio of meeting physical activity guidelines in health club members compared with non-members were 16 were aerobic, 10.1 for resistance and 13.8 for both aerobic and resistance.

The researchers found that health club membership was associated with significantly lower odds of elevated resting heart rate and obesity after they adjusted for potential confounders. Health club members also had lower odds of hypertension and abdominal obesity, although the differences were not statistically significant.

A multivariable linear regression analysis found that health club members had a 4.8 beats per minutes lower resting heart rate and a 2.1 mL/kg/min higher cardiorespiratory fitness after adjusting for potential confounders. They also had less sedentary time and a smaller waist circumference compared with non-members.

The researchers noted that the study had a few limitations, including that its cross-sectional design prohibits causal inferences. They noted that it was possible more active individuals purchased health club memberships. In addition, most of the participants were white and well-educated and lived in the same town, so the results might not be generalizable to other groups.

“With the declining average monthly fee for health club membership and the increasing support from employers and insurance companies, this study supports that promoting [physical activity] at a health club could be an effective public health strategy for health promotion and potentially health care cost reduction,” the researchers wrote. “However, large longitudinal, randomized controlled trials are clearly warranted to confirm our findings.”