Physical Activity and Insulin Resistance in 6,500 NHANES Adults: The Role of Abdominal Obesity

Table 1

Descriptive characteristics of the sample (n = 6500).

Variable	N	Weighted %	SE
Race
Non-Hispanic White	3371	73.0	1.5
Non-Hispanic Black	1190	10.4	0.9
Mexican American	1463	7.6	0.8
Other races	213	4.3	0.4
Other Hispanic categories	263	4.7	0.9
Gender
Men	3090	47.8	0.5
Women	3410	52.2	0.5
Waist circumference
Small	1447	25.0	0.6
Medium	1555	25.0	0.7
Large	1775	25.0	0.7
Extra-large	1723	25.0	0.7
Body mass index
Underweight	108	2.1	0.2
Normal weight	2058	34.4	0.8
Overweight	2331	34.2	0.9
Obese	2003	29.4	0.8
Physical activity (relative)
Sedentary-R	2640	34.0	1.0
Low-R	1354	22.5	0.8
Moderate-R	1309	22.1	0.7
High-R	1197	21.4	0.8
Physical activity (guidelines)
Sedentary-G	2640	34.0	1.0
Low-G	1326	21.7	0.7
Moderate-G	809	13.7	0.5
High-G	529	9.3	0.5
Very High-G	1196	21.3	0.8

Note: values in the column, weighted %, reflect the distribution of participants after the NHANES sample weights were applied. The physical activity-relative categories were based on the distribution of MET-minute levels for the present NHANES sample. Specifically, participants reporting no regular physical activity were classified as Sedentary, and the remaining adults, each reporting some physical activity in the past 30 days, were divided into sex-specific tertiles. The physical activity-guidelines categories were based on the 2018 US Physical Activity Guidelines. Specifically, Sedentary-G included those reporting no regular physical activity, Low-G included those performing some regular activity, but not reaching the minimum standards of the guidelines, and Moderate-G included those performing ≥500 and <1000 MET-minutes of activity per week, High-G included those performing ≥1000 and <1500 MET-minutes, and Very High-G included those performing ≥1500 MET-minutes of activity per week. Age and smoking (pack-years) were treated as continuous variables in the analyses.