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According to previous reports, obesity especially visceral fat has become an important public health problem, causing an estimation of 20.5 disability-adjusted life years per 1000 inhabitants. Those who exercised for 1 or 2 days per week and reached the recommended 150 minutes of moderate physical activity (PA) per week have been defined as “weekend warriors” (WWs). Although the benefits of PA in suppressing obesity have been widely studied, the association of WWs with the Visceral Adiposity Index (VAI) and the difference between WW activity and regular PA are yet to be explored.
This study aims to explore the association between WW activity and other PA patterns with VAI in US adults.
The National Health and Nutrition Examination Survey 2007-2016 data set was used, and the analytic sample was limited to adults 20 years and older who had complete information about VAI, PA patterns, and other covariates, including demographic characteristics, behavioral factors, and disease conditions. Participants’ characteristics in different PA pattern groups were tested using the Rao and Scott adjusted
The final sample included 9642 adults 20 years or older, which is representative of 158.1 million noninstitutionalized US adults, with 52.15% (n=5169) being male and 70.8% (n=4443) being non-Hispanic White. Gender, age group, race, education level, income level, marital status, smoking status, alcoholism, VAI, cardiovascular disease, and diabetes were all correlated with the PA pattern, but no relationship between hypertension and PA pattern was observed. After adjusting for demographic covariates, smoking status, alcoholism, cardiovascular disease, diabetes, and hypertension, WW and regularly active adults had a β of .307 (95% CI –0.611 to –0.003) and .354 (95% CI –0.467 to –0.241), respectively, for reduced VAI when compared with inactive adults, but no significant effect of lowering VAI (β=–.132, 95% CI –0.282 to 0.018) was observed in insufficiently active adults when compared with inactive adults. Besides, no significant difference was exhibited between WW adults and regularly active adults (β=.047, 95% CI –0.258 to 0.352), suggesting WW adults had the same benefit of decreasing VAI as regularly active adults. Stratified analyses results exhibited that WW activity was related to reduced VAI in female adults aged 20-44 years who were non-Hispanic Black, other, or multiracial; high school or General Educational Development education; and never married, and the association between PA pattern and VAI remained stable in all demographic subgroups.
Compared with inactive adults, WWs could reduce VAI, and there was no significant difference between WWs and regular active adults in decreasing VAI. Our study provides compelling evidence of the beneficial effect of WW activity on visceral obesity.
Physical activity (PA) has been proven to be beneficial by a number of studies, including for reducing chronic disease risk, improving mental state, and prolonging life [
In contrast to those who did 30 minutes of moderate-intensity PA for 5 days per week, those who did all exercise on 1 or 2 days per week were usually defined as “weekend warriors” (WWs) [
According to previous reports, obesity, especially visceral fat, has become an important public health problem, causing an estimation of 20.5 disability-adjusted life years per 1000 inhabitants. The economic impact of care for comorbidities associated with obesity could amount to US $2.158 billion. [
Therefore, we obtained data from the National Health and Nutrition Examination Survey (NHANES) to conduct an analysis concerning WW activity and VAI. Through this research, we would like to make the public aware of the benefits of PA on VAI and make suggestions on how to reduce VAI to further reduce various metabolic disease risks. At the same time, the impact of different modes of PA on VAI is an interesting research direction. We also used large-scale data to analyze the different PA modes and VAI so as to provide guidance on the choice of PA mode.
Data was derived from the six continuous NHANES cycles from 2007-2008 to 2017-2018, which is a nationally representative population-based survey for assessing adult and child health and nutritional status in the United States [
The total sample size of adults from the 2007 to 2018 cycle was 9642. Additional details on the study design, sampling, and exclusion criteria are described in
Flowchart of study design. NHANES: National Health and Nutrition Examination Survey; VAI: Visceral Adiposity Index.
All participants in NHANES provide informed consent and NHANES is approved by the research ethics review board of the Centers for Disease Control and Prevention [
The VAI was measured with the following sex-specific formula: VAI = [waist circumference (WC) / 39.68 + (1.88 * BMI)] * (triglycerides / 1.03) * (1.31 / high-density lipoprotein cholesterol [HDL-C]) for males and VAI = [WC / 36.58 + (1.89 * BMI)] * (triglycerides / 0.81) * (1.52 / HDL-C) for females, in which triglycerides and HDL-C were expressed in mmol/L, WC expressed in cm, and BMI expressed in kg/m2 [
PA in this study was assessed with a PA questionnaire in which participants were asked about the frequency and duration of vigorous and moderate sports, fitness, and recreational activities for at least 10 continuous minutes in a typical week. PA was calculated with the combination of frequency (times per week) and duration (duration per time), and total PA was calculated with the formula 2 * vigorous PA + moderate PA, since 1 minute of vigorous-intensity activity was defined as equivalent to 2 minutes of moderate-intensity activity according to PA guidelines [
Based on previous studies, covariates in this study included demographic data such as gender (male, female), age (20-44, 45-64, ≥65 years), race (non-Hispanic White, non-Hispanic Black, Mexican Americans, and other or multiracial races), education level (less than high school graduate, high school degree or equivalent, more than high school degree), income level (measured with as the ratio of family income to poverty [PIR]: low income PIR≤1.3, middle income 1.3<PIR<3.5, or high income PIR≥3.5), marital status (married or living with partner; divorced, separated, or widowed; never married). Behavioral risk factors included smoking status (never smoked, former smoker, current smoker) and alcoholism (yes, no). CVD was defined as a self-reported congestive heart failure, coronary heart disease, angina, myocardial infarction, or stroke diagnosed by a professional doctor. Diabetes was defined as a fasting plasma glucose ≥126 mg/dL, 2-hour plasma glucose ≥200 mg/dL, hemoglobin A1c ≥6.5%, or self-reported diabetes diagnosed by a professional doctor. Hypertension was defined as an average systolic pressure ≥140 mm Hg and diastolic pressure ≥90 mm Hg in 3 tests [
According to analytic guidelines published by the National Center for Health Statistics, stratum and primary sampling units were taken into account for the complex, multistage, probability sampling design. Since 6 consecutive cycles were derived from NHANES, the 2-year mobile examination center weight divided by 6 was adopted to be representative of the general population.
Initially, participants’ characteristics in different groups were tested using the Rao and Scott [
As described in
The characteristics of participants in different PA pattern groups are presented in
Participants characteristics according to physical activity pattern.
Characteristics | Overall (n=9642) | Inactive (n=4854) | Insufficiently active (n=1474) | Weekend warrior (n=190) | Regularly active (n=3124) | |||
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<.001 | |||||||
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Male | 5169 (52.15) | 2543 (50.70) | 704 (47.96) | 151 (73.45) | 1771 (54.69) |
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Female | 4473 (47.85) | 2311 (49.30) | 770 (52.04) | 39 (26.55) | 1353 (45.31) |
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<.001 | |||||||
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20-44 | 4074 (44.82) | 1694 (38.09) | 625 (44.00) | 146 (51.70) | 4609 (51.70) |
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45-64 | 3424 (37.78) | 1877 (41.42) | 536 (38.23) | 40 (33.98) | 971 (33.98) |
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≥65 | 2144 (17.40) | 1283 (20.49) | 313 (17.77) | 4 (0.02) | 544 (14.32) |
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<.001 | |||||||
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Non-Hispanic White | 4443 (70.80) | 2192 (68.37) | 704 (74.21) | 56 (56.44) | 1491 (73.00) |
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Non-Hispanic Black | 1877 (9.43) | 979 (10.53) | 278 (8.30) | 49 (14.54) | 571 (8.34) |
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Mexican American | 1398 (8.08) | 786 (9.50) | 180 (6.42) | 38 (12.87) | 394 (6.84) |
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Other or multiracial | 1924 (11.69) | 897 (11.61) | 312 (11.07) | 47 (16.16) | 668 (11.83) |
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<.001 | |||||||
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Less than high school graduate | 2119 (14.26) | 1508 (22.15) | 209 (9.41) | 41 (17.34) | 361 (6.65) |
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High school graduate | 2226 (22.49) | 1248 (27.14) | 329 (21.90) | 45 (19.08) | 604 (17.26) |
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Some college or above | 5297 (63.25) | 2098 (50.71) | 936 (68.69) | 104 (63.58) | 2159 (76.08) |
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<.001 | |||||||
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PIRa≤1.3 | 2916 (20.30) | 1818 (27.11) | 345 (15.78) | 60 (23.01) | 693 (13.88) |
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1.3<PIR<3.5 | 3660 (35.41) | 1933 (38.94) | 568 (35.15) | 76 (40.50) | 1083 (30.92) |
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PIR≥3.5 | 3066 (44.29) | 1103 (33.95) | 561 (49.07) | 54 (36.48) | 1348 (55.20) |
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<.001 | |||||||
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Married or living with partner | 5845 (64.72) | 2949 (64.26) | 912 (66.87) | 104 (55.50) | 1880 (64.80) |
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Divorced, separated, or widowed | 2068 (17.80) | 1201 (21.02) | 312 (16.70) | 23 (12.00) | 532 (14.69) |
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Never married | 1729 (17.48) | 704 (14.73) | 250 (16.43) | 63 (32.51) | 712 (20.51) |
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<.001 | |||||||
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Never | 4800 (51.12) | 2168 (45.36) | 779 (53.79) | 113 (63.09) | 1740 (56.30) |
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Former | 2649 (27.82) | 1343 (27.18) | 425 (29.20) | 28 (14.75) | 853 (28.67) |
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Current | 2193 (21.07) | 1343 (27.46) | 270 (17.01) | 49 (22.16) | 531 (15.03) |
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<.001 | |||||||
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No | 7982 (83.85) | 3858 (79.79) | 1256 (85.23) | 164 (87.88) | 2704 (87.98) |
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Yes | 1660 (16.15) | 996 (20.21) | 218 (14.77) | 26 (12.12) | 420 (12.02) |
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<.001 | |||||||
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No | 8637 (91.85) | 4199 (89.12) | 1348 (93.72) | 184 (98.70) | 2906 (93.97) |
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Yes | 1005 (8.15) | 655 (10.88) | 126 (6.28) | 6 (1.30) | 218 (6.03) |
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<.001 | |||||||
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No | 7689 (85.04) | 3615 (79.69) | 1213 (87.48) | 178 (94.75) | 2683 (89.95) |
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Yes | 1953 (14.96) | 1239 (20.31) | 261 (12.52) | 12 (5.25) | 441 (10.05) |
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.17 | |||||||
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No | 9355 (97.44) | 4697 (97.23) | 1425 (96.72) | 184 (98.12) | 3049 (97.99) |
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Yes | 287 (2.56) | 157 (2.77) | 49 (3.28) | 6 (1.88) | 75 (2.01) |
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Visceral Adiposity Index, |
1.98 (2.61) | 2.24 (3.04) | 1.95 (1.84) | 1.71 (1.72) | 1.68 (2.33) | <.001 |
aPIR: ratio of family income to poverty.
The results of the binary univariate and multivariate logistic regression models of PA pattern on VAI were presented in
The relationship between physical activity pattern and Visceral Adiposity Index in adults.
Characteristics | Model 1a | Model 2b | Model 3c |
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β (95% CI) | β (95% CI) | β (95% CI) |
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Inactive | Reference | N/Ad | Reference | N/A | Reference | N/A |
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Insufficiently active | –.291(–0.463 to –0.118) | .001 | –.212 (–0.374 to –0.049) | .01 | –.132 (–0.282 to 0.018) | .08 |
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Weekend warrior | –.535 (–0.830 to –0.239) | .001 | –.434 (–0.732 to –0.135) | .005 | –.307 (–0.611 to –0.003) | .04 |
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Regularly active | –.557 (–0.671 to –0.443) | <.001 | –.441 (–0.556 to –0.326) | <.001 | –.354 (–0.467 to –0.241) | <.001 |
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Regularly active | Reference | N/A | Reference | N/A | Reference | N/A |
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Inactive | .557 (0.443 to 0.671) | <.001 | .440 (0.326 to 0.556) | <.001 | .354 (0.241 to 0.468) | <.001 |
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Insufficiently active | .266 (0.106 to 0.426) | .001 | .229 (0.063 to 0.395) | .007 | .222 (0.060 to 0.385) | .008 |
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Weekend warrior | .022 (–0.287 to 0.332) | .89 | .007 (–0.294 to 0.309) | .96 | .047 (–0.258 to 0.352) | .76 |
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aModel 1 was the univariate model in which no covariates were adjusted.
bModel 2 was adjusted for demographic covariates, including gender, age group, race, education level, income level, and marital status.
cModel 3 was additionally adjusted for smoking status, alcoholism, cardiovascular disease, diabetes, and hypertension.
dN/A: not applicable.
The forest plot of PA pattern and the Visceral Adiposity Index in adults. PA: physical activity.
To better understand the association between PA pattern and VAI in various subgroups, we conducted stratified analyses according to demographic characteristics. As described in
The relationship between physically activity pattern and Visceral Adiposity Index in subgroupsa.
Characteristics | Inactive | Insufficiently active, β (95% CI) | Weekend warrior, β (95% CI) | Regularly active, β (95% CI) | |||||||
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.17 | ||||||||||
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Male | Reference | –.123 (–0.363 to 0.118) | –.229 (–0.636 to 0.177) | –.373 (–0.547 to –0.199) |
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Female | Reference | –.152 (–0.334 to 0.030) | –0.621 (–0.902 to –0.339) | –.327 (–0.502 to –0.151) |
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.61 | ||||||||||
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20-44 | Reference | –.262 (–0.483 to –0.041) | –.388 (–0.776 to 0.000) | –.425 (–0.603 to –0.247) |
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45-64 | Reference | –.055 (–0.361 to 0.250) | –.314(–0.883 to 0.259) | –.269 (–0.558 to 0.021) |
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≥65 | Reference | –.053 (–0.345 to 0.240) | –.251 (–0.608 to 0.107) | –.375 (–0.554 to –0.195) |
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.28 | ||||||||||
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Non-Hispanic White | Reference | –.148(–0.345 to 0.049) | –.270 (–0.744 to 0.204) | –.390 (–0.548 to –0.233) |
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Non-Hispanic Black | Reference | –.136 (–0.316 to 0.045) | –.345 (–0.600 to –0.089) | –.236 (–0.447 to –0.026) |
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Mexican American | Reference | –.414 (–0.744 to –0.083) | –.384 (–1.430 to 0.661) | –.198 (–0.578 to 0.183) |
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Other or multiracial | Reference | .093 (–0.243 to 0.429) | –.493 (–0.928 to –0.059) | –.370 (–0.615 to –0.125) |
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.99 | ||||||||||
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Less than high school graduate | Reference | –.243 (–0.539 to 0.053) | –.154 (–0.722 to 0.414) | –.369 (–0.684 to –0.053) |
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High school graduate or GEDb | Reference | –.241 (–0.533 to 0.052) | –.446 (–0.805 to –0.086) | –.361 (–0.596 to –0.125) |
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Some college or above | Reference | –.098 (–0.300 to 0.105) | –.271 (–0.727 to 0.184) | –.351 (–0.499 to –0.202) |
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.58 | ||||||||||
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PIRc≤1.3 | Reference | –.293 (–0.541 to –0.044) | –.225 (–0.660 to 0.211) | –.414 (–0.651 to –0.177) |
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1.3<PIR<3.5 | Reference | –.111 (–0.388 to 0.166) | –.166 (–0.781 to 0.450) | –.220 (–0.474 to 0.034) |
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PIR≥3.5 | Reference | –.108 (–0.323 to 0.107) | –.392 (–0.822 to 0.037) | –.429 (–0.587 to –0.272) |
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.16 | ||||||||||
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Married or living with partner | Reference | –.099 (–0.295 to 0.097) | –.188 (–0.722 to 0.347) | –.448 (–0.603 to –0.295) |
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Divorced, separated, or widowed | Reference | –.255 (–0.541 to 0.032) | –.287 (–0.767 to 0.194) | –.145 (–0.478 to 0.188) |
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Never married | Reference | –.121 (–0.474 to 0.231) | –.412 (–0.657 to –0.167) | –.168 (–0.437 to 0.101) |
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aThe models were adjusted for demographic characteristics, behavioral factors, and disease conditions.
bGED: General Educational Development.
cPIR: ratio of family income to poverty.
With NHANES, we found that the WW exercise pattern in US adults is helpful to reduce VAI compared with no exercise. In particular, there was no difference between WWs and RA adults, suggesting that WW activity had the same VAI reduction effect as regular activity. Moreover, stratified analysis and interaction analysis confirmed the stability of the results. This might suggest for people who cannot exercise regularly that WW activity could reduce visceral obesity and improve health.
To the best of our knowledge, this is the first analysis to explore the impact of PA patterns, especially of WWs, on VAI. At present, most studies focus on the influence of the sedentary behaviors and leisure time PA (LTPA) ratio on disease or health status [
We took inactivity as the reference. In model 1, no covariates were considered, and insufficiently active, WW, and RA adults had reduced VAI. In model 2, after adjusting for demographic data, the results were similar to the univariate analysis. In model 3, WW and RA adults had reduced VAI after adjusting for demographic data, behavioral factors, and disease conditions, while no significant difference was observed in insufficiently active adults and inactive adults. In detail, RA adults had the largest negative correlation with VAI (β=–.35;
Moreover, the linear regression showed other influencing factors of VAI (see
Our results showed that non-Hispanic Black participants were more likely to reduce VAI than non-Hispanic White participants. Some studies found that, after correcting for total fat mass, Black women had less visceral adipose tissue than White women, while White people had more visceral adipose tissue than African American people [
There was no difference between middle-income and low-income groups on VAI, while the VAI of the high-income group was significantly lower than that of the low-income group. Ameye and Swinnen [
Unmarried people were more likely to reduce VAI than married people. According to Lee et al [
Smokers might have higher VAI than nonsmokers. Wehby et al [
Participants who were diabetic could increase VAI more than those without diabetes. According to Haslam’s [
VAI has been proven by many studies to be a predictor of cardiovascular and metabolic diseases such as hypertension, T2DM, CVD, and nonalcoholic fatty liver disease. Therefore, we planned to conduct a structural equation model in the next study to analyze the mediation effect of VAI: whether the activity pattern might affect VAI and related diseases. This future research direction would improve the relationship between exercise, diet, and visceral obesity, and further specify the analysis of activity and diet patterns.
There were several advantages in this study. First, we adopted a large-scale data set including 9642 participants, thus ensuring representativeness. Second, the topic of activity and obesity was specified in this study, thus the association between visceral obesity and different exercise modes. Finally, this study used a hierarchical linear regression method to analyze the covariates of VAI in detail. However, there were still some limitations. First, this study was based on a cross-sectional investigation, which could not infer the causal relationship between activity patterns and VAI. Second, there are many factors related to VAI, and the variables included in this study are limited. Third, since this study focused on the activity patterns, it did not further explore the relationship between exercise intensity, exercise/sedentary ratio, and VAI, which could be explored in the next study.
In conclusion, although the benefits of physical activities were well known, many people had limited time to engage in activities, and MVPA only accounted for 5% of the total time for daytime activities. Therefore, the role of WW activity is worth researching. According to our results, we found that, compared with no activity, WWs could reduce VAI, and there was no difference between WWs and RA adults, indicating that WW activity is worth promoting for people who cannot exercise regularly. This research also suggested that the duration of PA was more important than the frequency of activity. With this study, we want to make the public aware of the benefits about WW PA and encourage those who are tired from work but want to keep healthy to exercise during the weekend to reduce VAI.
Other risk factors of Visceral Adiposity Index.
cardiovascular disease
high-density lipoprotein cholesterol
leisure time physical activity
moderate-to-vigorous physical activity
National Health and Nutrition Examination Survey
physical activity
ratio of family income to poverty
regularly active
type 2 diabetes mellitus
Visceral Adiposity Index
waist circumference
weekend warrior
The data sets were derived from NHANES 2007-2008 to 2017-2018 [
None declared.