Cardiorespiratory fitness and body mass index on metabolic syndrome in middle-aged Japanese adults under national health guidance: a cross-sectional study.

OBJECTIVES: Poor cardiorespiratory fitness (CRF) and high body mass index (BMI) increased the risk of developing metabolic Syndrome (MetS) mostly in Caucasians. However, the sex-specific combined association of CRF and BMI on MetS considering health-related behaviors has yet to be thoroughly examined in Japanese. This study aims to investigate the sex-specific independent and combined associations of CRF and BMI with MetS in middle-aged Japanese adults. METHODS: 421 participants were included in this cross-sectional study. CRF was estimated using a submaximal cycle ergometer. CRF and BMI were respectively divided into three categories according to tertile distribution. MetS was diagnosed based on five risk factors: waist circumference, triglycerides, high-density lipoprotein cholesterol, blood pressure, and fasting glucose. Multivariable logistic regression models were used to estimate independent and combined association of CRF and BMI with MetS. RESULTS: Results showed that 154 (57.5%) and 70 (45.8%) of men and women had MetS, respectively. Compared to men with lower CRF or higher BMI, men with middle and higher CRF or middle and lower BMI were less likely to have MetS. Compared with 'unfit and higher BMI' group, 'unfit and lower BMI', 'fit and higher BMI', and 'fit and lower BMI' groups in men showed statistically significant decreased prevalences of MetS. However, no significant associations were found in women. CONCLUSIONS: This study found significant independent and combined associations of CRF and BMI with MetS only in men, but not in women. However, prospective studies are warranted to confirm sex-specific associations of CRF and BMI with MetS.

Impact of COVID-19 Pandemic Lockdown on Body Mass Index and Physical Fitness in Chinese College Students.

PURPOSE: To explore the impact of COVID-19 pandemic lockdown (CoPL) on body mass index (BMI) and physical fitness among college students. METHODS: Two one-year cohorts, one with no pandemic lockdown (NoPL) exposure and one with CoPL exposure, were included. Baseline measurements were performed in October 2018 (NoPL) and October 2019 (CoPL), and follow-up data were collected one year later. Participants were divided into "deterioration", "no-change", and "improvement" groups based on their quartile distribution of one-year differences (follow-up-baseline) for lower 25%, middle 50%, and upper 25%. Baseline-category logit regression models were used to determine the odds ratios of deterioration and improvement in BMI and physical fitness, with "no-change" used as baseline. RESULTS: A total of 2,594 and 2,525 students were included in NoPL and CoPL cohorts, respectively. CoPL was associated with higher odds for deterioration in BMI (male), explosive strength, upper-limb muscle strength, abdominal muscle strength, and cardiorespiratory fitness, but lower odds for deterioration in BMI (female) and flexibility. CoPL was associated with lower odds for improvement in BMI (male), explosive strength, lower-limb and upper-limb muscle strength, and cardiorespiratory fitness, but higher odds for improvement in BMI (female) and flexibility. DISCUSSION: Not all dimensions of health outcomes were negatively impacted by the lockdown, as deterioration in BMI in males, muscle strength, and cardiorespiratory fitness following the CoPL were more than that in the absence of the lockdown, while deterioration in BMI in females and flexibility were less than that in the absence of the lockdown.