The Association of Sudarshan Kriya Yoga with Happiness: A Case-Control Observational Study from Singapore.

Happiness is a complex subjective experience that is essential to societal progress. This study investigated the association between Sudarshan Kriya Yoga (SKY) and subjective happiness in Singapore. Subjective happiness data were collected from a convenience sample (N = 733) comprised of 2 groups: SKY (n = 385) and non-SKY (n = 348) practitioners. SKY was categorized into non-, monthly, weekly, and daily practitioners and happiness was categorized into lower, middle and higher tertile groups. Confounding variables included age, gender, ethnicity, marital status, education level, body mass index (BMI), smoking status, alcohol consumption and self-reported health. Daily SKY participation was positively associated with a 2-fold higher likelihood of being happier in a multivariate regression analysis. The trend analysis showed that as SKY frequency increases, the odds of being happier increases. These findings help generate the hypothesis that yogic breathing may promote happiness. Further experimental and prospective investigations are warranted.

The association of fitness and fatness with intermediate hyperglycemia incidence in women: A cohort study.

The purpose of this study was to examine the associations of cardiorespiratory fitness, general adiposity, and central adiposity with incident intermediate hyperglycemia (IH) in women. We conducted a prospective cohort study of 1534 women aged 20-79 years old who had an annual health check-up with no history of major chronic diseases. At baseline, fitness was assessed by a Balke graded exercise test, and the estimated metabolic equivalents were used to create quartile groups. Women were also grouped based on their body mass index (<25 kg/m2, 25-29.9 kg/m2, and ≥ 30 kg/m2) and waist-to-height ratio (≥0.50 or < 0.50). Cox proportional hazards models were conducted to assess the association of fitness and fatness variables with incident IH defined as fasting glucose of 5.6-6.9 mmol/L. Overall, 18.1% (n = 277) of the women developed IH during an average follow-up of 5.06 years. Fitness, body mass index, and waist-to-height ratio at baseline were the independent predictors of the IH incidence in separate age-adjusted models; yet when all three variables were included in the same model along with confounding variables, only fitness remained significant and demonstrated a clear inverse association with incident IH (P-for-trend <0.001). Health promotion efforts should focus on improving fitness for the prevention of IH in women.

The association of Sudarshan Kriya Yoga frequency with sleep quality: a cross-sectional study from Singapore.

PURPOSE: There is a dearth of evidence for the relationship between yogic breathing and sleep quality. Even less is known about practice frequency and benefit. We investigated the association of Sudarshan Kriya Yoga frequency with sleep quality amongst adult practitioners. METHODS: In a cross-sectional investigation on adult practitioners of Sudarshan Kriya Yoga in Singapore, the Pittsburgh Sleep Quality Index (PSQI) was used to assess sleep quality. Sleep quality was examined across three categories of practice frequency (monthly, weekly, daily). A multivariate logistic regression model was used to determine association. RESULTS: Of 385 adults (241 women), the mean age (SD) was 42.5 (9.9) years. In total, 32% of the sample (n = 124) was identified as having poor SQ. After adjusting for study covariates, independent analyses revealed an inverse association for higher frequency of practice and lower odds of poor SQ (OR = 0.52; 95% CI = 0.28-0.94). The p for trend was 0.03. CONCLUSION: The practice of yogic breathing may benefit sleep quality. Further experimental investigations are warranted.

Importance of Achieving a "Fit" Cardiorespiratory Fitness Level for Several Years on the Incidence of Type 2 Diabetes Mellitus: A Japanese Cohort Study.

BACKGROUND: The "Physical Activity Reference for Health Promotion 2013" provides "fit" reference values for cardiorespiratory fitness (CRF) for good health. The importance of achieving a fit CRF level for several years on the subsequent prevention of type 2 diabetes mellitus (T2DM) remains to be clarified. METHODS: This cohort study was conducted in 2,235 nondiabetic males aged 21 to 59 years, enrolled in April 1986 through March 1987. We calculated the ratio of the area under the curve (AUCratio) for actual measured values and the AUC for the reference values of CRF in each individual during an 8-year measurement period before the baseline. According to whether they met a fit CRF level or not, participants were categorized into groups based on the AUCratio (FitAUC or UnfitAUC) and initial CRF (Fitinitial or Unfitinitial), respectively. T2DM was evaluated on health checkups until March 2010. RESULTS: During the follow-up period, 400 men developed T2DM. After adjustment for confounders, as compared with those in the FitAUC group, the hazard ratio (HR) for those in the UnfitAUC group was 1.33 (95% confidence interval [CI], 1.06-1.65). A combined analysis with the categories of initial value and AUCratio showed that, compared with the Fitinitial and FitAUC group, the HRs of Fitinitial and UnfitAUC, Unfitinitial and FitAUC, and Unfitinitial and UnfitAUC groups were 1.41 (95% CI, 0.99-2.00), 1.18 (95% CI, 0.81-1.70), and 1.40 (95% CI, 1.08-1.83), respectively. CONCLUSION: Achievement of a fit CRF level established in the Japan physical activity guideline for several years was associated with lower subsequent risk of T2DM.

Association between objectively measured physical activity and body mass index with low back pain: a large-scale cross-sectional study of Japanese men.

BACKGROUND: The relationship between the combination of physical activity (PA) and body mass index (BMI) with low back pain (LBP) is unclear. The present study offers a cross-sectional assessment of how combinations of PA and BMI are related to LBP in Japanese men. METHODS: Participants were 4022 Japanese men (mean age = 47) who underwent regular clinical examinations. PA was measured using a uniaxial accelerometer and divided into tertiles (PAhigh, PAmiddle, PAlow). A self-administered questionnaire was used to report on persistent LBP experience, drinking and smoking habits, and any existing lifestyle diseases. After covariance adjustment, a logistic regression model was used to assess how combinations of PA and BMI are related to persistent LBP. RESULTS: 428 of the participants had persistent LBP. A clear negative dose-response relationship was found between PA levels and persistent LBP (P for linearity = 0.012). Regarding BMI, odd ratios were shown to be higher in the overweight/obese category (BMI ≥ 25 kg/m2) than for the normal weight category (BMI < 25 kg/m2). When the PAhigh was taken as the reference in the normal weight category, odds ratios for PAlow and PAmiddle in the normal weight category were shown to be high. Moreover, in the overweight/obese category, odd ratios for every fitness level were also high as for the normal weight category. CONCLUSION: The present study showed that both PA and BMI are related to persistent LBP. Also, the prevalence of persistent LBP became higher when PAlow and high BMI are combined rather than the group of PAhigh and low BMI combination.

Combined association of fitness and central adiposity with health-related quality of life in healthy Men: a cross-sectional study.

BACKGROUND: There is limited data examining the association of combined fitness and central obesity with health related quality of life (HRQoL) in adults. We examined the association of combined cardiorespiratory fitness (CRF) and waist-to-height ratio (WHtR) in the form of a fit-fat index (FFI) with the Physical Component Summary (PCS) and Mental Component Summary (MCS) HRQoL scores in United States Navy servicemen. METHODS: As part of a health fitness assessment, a total of 709 healthy males aged 18-49 years completed a submaximal exercise test, WHtR measurement, and HRQoL survey (SF-12v2) between 2004 and 2006. FFI level was classified into thirds with the lowest FFI tertile serving as the referent group. PCS and MCS scores ≥50 were taken to indicate average or better. Logistic regression was used to obtain odds ratios (OR) and 95% confidence intervals (CI). RESULTS: The prevalence of average or better HRQoL scores was lowest in the referent FFI tertile, PCS 60.2% and MCS 57.6%. Compared with the lowest FFI group in multivariate analyses, the OR (95% CI) of having average or better PCS was 1.63 (1.09-2.42) and 3.12 (1.95-4.99) for moderate and high FFI groups respectively; MCS was 1.70 (1.13-2.55) and 4.89 (3.03-7.89) for moderate and high FFI groups respectively (all P < 0.001). Consistent and progressive independent associations were observed between age and MCS, and also between CRF and MCS. CONCLUSION: Among males in the United States Navy, higher levels of FFI were independently and more consistently associated with having average or better HRQoL (physical and mental) than other known predictors of HRQoL.

Estimated Cardiorespiratory Fitness and Metabolic Risks.

This review focuses on the emerging evidence for the association between non-exercise fitness testing, estimated cardiorespiratory fitness (eCRF), and metabolic risk factors. Given the challenges associated with directly measuring cardiorespiratory fitness (CRF) in large populations, eCRF presents a practical alternative for predicting metabolic health risks. A literature search identified seven relevant cohort studies from 2020 to 2024 that investigated the association of eCRF with hypertension, hyperglycemia, dyslipidemia, and obesity. This review consistently demonstrates an inverse relationship between higher eCRF and a lower incidence of metabolic risks, which is in line with CRF cohort studies. It highlights the importance of low eCRF as a primordial indicator for metabolic risks and underscores the potential for broader application. Future research directions should include exploring eCRF's predictive ability across diverse populations and health outcomes and testing its real-world applicability in healthcare and public health settings.

Associations of sedentary behavior and physical activity with psychological distress: a cross-sectional study from Singapore.

BACKGROUND: Emerging evidence suggests the adverse association between sedentary behaviour (SB) with physical and mental health, but few studies have investigated the relationship between volume of physical activity and psychological distress. The present study examined the independent and interactive associations of daily SB and weekly level of moderate to vigorous physical activity (MVPA) with psychological distress in a multi-ethnic Asian population. METHODS: De-identified data of 4,337 adults (18-79 years old) on sedentary behaviors, physical activity patterns, psychological distresses, and other relevant variables were obtained from the Singapore Ministry of Health's 2010 National Health Survey. Psychological distress was assessed using General Health Questionnaire-12 (GHQ-12), whereas total daily SB and total weekly volume (MET/minutes) of MVPA were estimated using the Global Physical Activity Questionnaire version 2 (GPAQ v2). Multivariate logistic regression analyses were carried out to estimate the odds ratios (95% confidence intervals) of the independent and interactive relationships of SB and MVPA with prevalence of psychological distress. RESULTS: The category of high SB was positively associated with increased odds (OR = 1.29, 1.04-1.59) for psychological distress, whereas the category of active was inversely associated with lower odds (OR = 0.73, 0.62-0.86) for psychological distress. Multivariate analyses for psychological distress by combined daily SB and weekly MVPA levels showed inverse associations between middle SB and active categories (OR = 0.58, 0.45 - 0.74) along with low SB and active categories (OR = 0.61, 0.47-0.80). CONCLUSIONS: The present population-based cross-sectional study indicated that in the multi-ethnic Asian society of Singapore, a high level of SB was independently associated with psychological distress and meeting the recommended guidelines for physical activity along with ≤ 5 h/day of SB was associated with the lowest odds of psychological distress.

Association between Estimated Cardiorespiratory Fitness and Abnormal Glucose Risk: A Cohort Study.

BACKGROUND: Cardiorespiratory fitness (CRF) is a predictor of chronic disease that is impractical to routinely measure in primary care settings. We used a new estimated cardiorespiratory fitness (eCRF) algorithm that uses information routinely documented in electronic health care records to predict abnormal blood glucose incidence. METHODS: Participants were adults (17.8% female) 20-81 years old at baseline from the Aerobics Center Longitudinal Study between 1979 and 2006. eCRF was based on sex, age, body mass index, resting heart rate, resting blood pressure, and smoking status. CRF was measured by maximal treadmill testing. Cox proportional hazards regression models were established using eCRF and CRF as independent variables predicting the abnormal blood glucose incidence while adjusting for covariates (age, sex, exam year, waist girth, heavy drinking, smoking, and family history of diabetes mellitus and lipids). RESULTS: Of 8602 participants at risk at baseline, 3580 (41.6%) developed abnormal blood glucose during an average of 4.9 years follow-up. The average eCRF of 12.03 ± 1.75 METs was equivalent to the CRF of 12.15 ± 2.40 METs within the 10% equivalence limit. In fully adjusted models, the estimated risks were the same (HRs = 0.96), eCRF (95% CIs = 0.93-0.99), and CRF (95% CI of 0.94-0.98). Each 1-MET increase was associated with a 4% reduced risk. CONCLUSIONS: Higher eCRF is associated with a lower risk of abnormal glucose. eCRF can be a vital sign used for research and prevention.

Association Between Sudarshan Kriya Yoga and Healthy Lifestyle Practices Among Working Adults: A Cross-Sectional Study from Singapore.

Objectives: There is a paucity of research on the association between yogic breathing and healthy lifestyle factors in working adults. Also, there is very little information about the frequency of yogic breathing practice and its benefits. The authors investigated the relationship between Sudarshan Kriya Yoga (SKY) frequency and the likelihood of leading a healthier lifestyle among practitioners and nonpractitioners. Design: Cross-sectional investigation on non-SKY and SKY practitioners, SKY was categorized into non-, monthly, weekly, and daily practitioners. Confounding variables included age, gender, ethnicity, marital status, and education level. A multivariate logistic regression model was used to compare practice frequencies with the odds of having a healthier lifestyle. Settings: Community centers, community events, workplaces, and universities throughout Singapore Subjects: Of the 531 working adults (54.8% female), 50.1% had a healthier lifestyle ≥ 4 healthy lifestyle factors). Outcome Measure: Having a healthier lifestyle was defined as having ≥ 4 healthy lifestyle factors out of seven (smoking, alcohol, diet, exercise, sleep, stress, and weight). Results: Multivariate analysis demonstrated that those who practiced SKY ≥ 4 days/week had significantly higher odds of having a healthier lifestyle (odds ratio = 3.62; 95% confidence interval = 2.10-6.23). The p for trend analysis demonstrated that as the frequency of practice increased the likelihood of having a healthier lifestyle also increased ( p < 0.001). Conclusion: The practice of yogic breathing may promote a healthier lifestyle in working adults. Further experimental and longitudinal investigations are warranted.

Accuracy of Non-Exercise Estimated Cardiorespiratory Fitness in Japanese Adults.

Cardiorespiratory fitness (CRF) is an independent predictor of morbidity and mortality. In Japan, annual physical exams are mandatory in workplace settings, and most healthcare settings have electronic medical records (EMRs). However, in both settings, CRF is not usually determined, thereby limiting the potential for epidemiological investigations using EMR data. PURPOSE: To estimate CRF (mL/kg/min) using variables commonly recorded in EMRs. METHODS: Participants were 5293 Japanese adults (11.7% women) who completed an annual physical exam at a large gas company in Tokyo, Japan, in 2004. The mean age was 48.3 ± 8.0 years. Estimated CRF (eCRF) was based on age, measured body mass index, resting heart rate, systolic and diastolic blood pressure, and smoking. Measured CRF was determined by a submaximal cycle ergometer graded exercise test. RESULTS: Regression models were used for males and females to calculate Pearson's correlation and regression coefficients. Cross-classification of measured CRF and eCRF was conducted using the lowest quintile, quartile, and tertile as the unfit categories. R's for eCRF were 0.61 (MD 4.41) for men and 0.64 (MD 4.22) for women. The overall accuracy level was reasonable and consistent across models, yet the unfit lower tertile model provided the best overall model when considering the positive predictive value and sensitivity. CONCLUSION: eCRF may provide a useful method for conducting investigations using data derived from EMRs or datasets devoid of CRF or physical activity measures.

Examining the day-to-day bidirectional associations between physical activity, sedentary behavior, screen time, and sleep health during school days in adolescents.

BACKGROUND: Adolescence is a vulnerable period for experiencing poor sleep health. Growing studies have demonstrated lifestyle behaviors including physical activity (PA), screen time (SCT), and sedentary behaviors (SED) as the potential factors associated with sleep health in adolescents; yet, the evidence is inconclusive and the directionality of temporal associations across school days are not well understood. This study examined the day-to-day bidirectional associations of lifestyle behaviors with sleep health parameters in adolescents. METHODS: A total of 263 adolescents (58% boys) in 6th - 8th grades wore an accelerometer for 24-hour across the three consecutive school days and completed recording SCT in time-diary and answering sleep quality (SQ) questions for each day. Sleep-wake patterns as well as time spent in moderate- and vigorous-intensity PA (MVPA) and SED were objectively quantified from the wrist-worn accelerometry data across the two segments of the day (during and after school hours). Mixed model analyses were conducted to test bidirectional associations between lifestyle factors and sleep health parameters in each temporal direction across the days. Additionally, indirect associations across the days were tested using an autoregressive cross-lagged model analysis in the framework of path analysis. RESULTS: MVPA minutes in a day did not predict sleep health parameters that night. The bidirectional associations were partially observed between SED and sleep health, but the significance and direction of the associations largely varied by the time segment of a day as well as types of sleep health parameters. Additionally, greater SCT during the day was associated with lower SQ that night (b = -0.010; P = .018), and greater SQ was associated with greater MVPA during school hours (b = 6.45; P = .028) and lower SED after school hours (b = -39.85; P = .029) the next day. Lastly, there were significant indirect associations of SCT with sleep health parameters across the days indicating multi-day lagged effects of SCT on sleep health the later nights. CONCLUSION: This study highlights the importance of lowering SCT for better sleep health in adolescents during school days. Additionally, perceived SQ is shown to be a potential significant predictor promoting healthy behaviors the next day independent of sleep-wake patterns. Further studies are warranted to confirm the observed temporal associations between SCT, SQ, and behavioral outcomes in this vulnerable population.

Clarifying differences in viewpoints between multiple healthcare professionals during discharge planning assessments when discharging patients from a long-term care hospital to home.

Comprehensive discharge planning provided by interprofessional collaboration is critical for discharging patients from hospitals to home. For effective interprofessional discharge planning, the evaluation that clarifies the differences in assessment viewpoints between various healthcare professionals is needed. This study aimed to clarify the assessment viewpoints of multiple healthcare professional groups when discharging patients from a long-term care hospital (LTCH) to home. We reviewed 102 medical records from an LTCH in Japan, extracted descriptions of discharge planning assessments written by 3 doctors, 13 nurses, 3 physical therapists, 13 care workers, and 2 social workers, linked these to the International Classification of Functioning, Disability and Health, and conducted the statistical analysis. Doctors and nurses significantly focused on "Body Functions". Physical therapists and care workers significantly focused on "Activities and Participation". Social workers significantly focused on "Environmental Factors". We also identified the factors less or missing from assessments in the clinical field of the LTCH. Our findings could be contributed as a base of knowledge to foster a better understanding of different healthcare professionals' assessment viewpoints. The further development of comprehensive discharge planning assessment tools, service programs, and research on discharge planning methods that could contribute to effective interprofessional discharge planning is needed.

Is Less Sedentary Behavior, More Physical Activity, or Higher Fitness Associated with Sleep Quality? A Cross-Sectional Study in Singapore.

OBJECTIVES: To examine the independent, joint, and fully combined associations of sedentary behavior (SB), moderate-to-vigorous physical activity (MVPA), and cardiorespiratory fitness (CRF) with the odds of poor sleep quality (SQ). METHODS: We performed a secondary data analysis on 757 working adults (male = 345) in Singapore, with an average age of 35.2 years. The Pittsburgh Sleep Quality Index was used to assess SQ. Objectively measured MVPA and SB were each obtained using an accelerometer. A non-exercise prediction equation was used to estimate CRF. Logistic regression models were used to determine associations. RESULTS: In total, 13.2% of the sample (n = 100) was identified as having poor SQ. After adjusting for study covariates, independent analyses revealed a clear inverse association for higher CRF and lower odds of poor SQ (OR = 0.50; 95% CI = 0.28-0.91). SB and MVPA demonstrated no independent associations. Joint associations revealed that odds of having poor SQ for those with low CRF was higher regardless of SB level and was further deteriorated by lower MVPA in the fully combined model. The fully combined model also demonstrated that those with lower SB, higher MVPA, and higher CRF had the lowest odds of having poor SQ (OR = 0.28; 95% CI = 0.10-0.78). CONCLUSIONS: Physical activity/exercise training programs that aim to improve CRF may be useful in lowering the odds or poor SQ in working adults.

Associations between cardiorespiratory fitness and health-related quality of life.

BACKGROUND: There is limited data examining the association between cardiorespiratory fitness (CRF) and health related quality of life (HRQOL) in healthy young adults. We examined the association between CRF and the HRQOL Physical Component Summary (PCS) and Mental Component Summary (MCS) scores in apparently healthy males in the United States Navy. METHODS: A total of 709 males (18-49 yr) performed a submaximal exercise test and HRQOL assessment (SF-12v2) between 2004-2006. CRF level was classified into fourths depending on age distribution with the lowest fitness quartile serving as the referent group. PCS and MCS scores >or= 50 were defined as above the norm. Logistic regression was used to obtain odds ratios (OR) and 95% confidence intervals (CI). RESULTS: The age-standardized prevalence of above the norm scores was lowest in the referent CRF quartile, PCS 56.6% and MCS 45.1%. After adjusting for age, systolic blood pressure, body mass index, smoking habit, alcohol habit and using the lowest CRF group as the reference, the OR (95% CI) for PCS scores above the norm across the fitness quartiles (P < 0.003 for trend) were 1.51(0.94-2.41), 2.24(1.29-3.90), and 2.44 (1.30-4.57); For MCS the OR (95% CI) were across the fitness quartiles (P trend < 0.001) 2.03(1.27-3.24), 4.53(2.60-7.90), 3.59(1.95-6.60). CONCLUSION: Among males in the United States Navy relative higher levels of CRF are associated with higher levels of HRQOL.

Frequency of achieving a 'fit' cardiorespiratory fitness level and hypertension: a cohort study.

OBJECTIVES: Although maintaining cardiorespiratory fitness is encouraged to reduce the risk of hypertension, the level at, and length of time for which, individuals need to maintain fitness remains unclear. We examined the association between the frequency of achieving the recommended fitness levels of the 'Physical Activity Reference for Health Promotion 2013' and the risk of hypertension among Japanese men. METHODS: This cohort study was conducted in 6653 men without hypertension enrolled in 1986. Whether the participants' fitness level was equal to or exceeded the reference value (fit) or not (unfit) was determined. The frequency of achieving the recommended fitness level was calculated by counting the number of times the fitness level was achieved in 1980 through 1986. Incident hypertension was defined as the first visit with a SBP/DBP of at least 140/90 mmHg or self-reported antihypertensive medication use and was evaluated during annual health examinations from 1986 until 2009. RESULTS: During the follow-up period, 3630 men developed hypertension. The multivariable-adjusted hazard ratios (95% confidence interval) for incident hypertension comparing men with fit versus unfit at baseline was 0.79 (0.74-0.85). Moreover, the frequency of achieving the recommended fitness level was inversely associated with the incidence of hypertension. The risk of hypertension was lower among those who achieved three or more of the recommended levels (0.72 for three times to 0.62 for seven times). CONCLUSION: Achieving the fitness level recommended in the Japanese guideline three or more times during a 6-year period can be beneficial for the risk reduction of hypertension.

The influence of a consumer-wearable activity tracker on sedentary time and prolonged sedentary bouts: secondary analysis of a randomized controlled trial.

OBJECTIVE: A recent meta-analysis surmised pedometers were a useful panacea to independently reduce sedentary time (ST). To further test and expand on this deduction, we analyzed the ability of a consumer-wearable activity tracker to reduce ST and prolonged sedentary bouts (PSB). We originally conducted a 12-month randomized control trial where 800 employees from 13 organizations were assigned to control, activity tracker, or one of two activity tracker plus incentive groups designed to increase step count. The primary outcome was accelerometer measured moderate-to-vigorous physical activity. RESULTS: We conducted a secondary analysis on accelerometer measured daily ST and PSB bouts. A general linear mixed model was used to examine changes in ST and prolonged sedentary bouts, followed by between-group pairwise comparisons. Regression analyses were conducted to examine the association of changes in step counts with ST and PSB. The changes in ST and PSB were not statistically significant and not different between the groups (P < 0.05). Increases in step counts were concomitantly associated with decreases in ST and PSB, regardless of intervention (P < 0.05). Caution should be taken when considering consumer-wearable activity trackers as a means to reduce sedentary behavior. Trial registration NCT01855776 Registered: August 8, 2012.

The Association of Fit-Fat Index with Incident Diabetes in Japanese Men: A Prospective Cohort Study.

Type 2 diabetes is increasing globally and in Asia. The purpose of this study was to examine the association of a fit-fat index (FFI) with diabetes incidence among Japanese men. In total 5,014 men aged 18-64 years old, who had an annual health check up with no history of major chronic disease at baseline from 2002 to 2009 were observed. CRF was estimated via cycle ergometry. Overall, 7.6% of the men developed diabetes. The mean follow-up period was 5.3 years. Hazard ratios, 95% confidence intervals and P trend for diabetes incidence were obtained using the Cox proportional hazards model while adjusting for confounding variables. High FFI demonstrated lower risk 0.54 (0.36-0.82) compared to low BMI 0.63 (0.44-0.90), low WHtR 0.64 (0.41-1.02), and High CRF 0.72 (0.51-1.03). FFI showed a marginally stronger dose response relationship across quartiles (P (trend) =0.001) compared to BMI (P (trend) =0.002), WHtR (P (trend) =0.055), and CRF (P (trend) =0.005). Overall, both fitness and fatness play independent roles in determining diabetes incidence in Japanese men. FFI may be a more advantageous physical fitness measure because it can account for changes in fitness and/or fatness.

Effectiveness of activity trackers with and without incentives to increase physical activity (TRIPPA): a randomised controlled trial.

BACKGROUND: Despite the increasing popularity of activity trackers, little evidence exists that they can improve health outcomes. We aimed to investigate whether use of activity trackers, alone or in combination with cash incentives or charitable donations, lead to increases in physical activity and improvements in health outcomes. METHODS: In this randomised controlled trial, employees from 13 organisations in Singapore were randomly assigned (1:1:1:1) with a computer generated assignment schedule to control (no tracker or incentives), Fitbit Zip activity tracker, tracker plus charity incentives, or tracker plus cash incentives. Participants had to be English speaking, full-time employees, aged 21-65 years, able to walk at least ten steps continuously, and non-pregnant. Incentives were tied to weekly steps, and the primary outcome, moderate-to-vigorous physical activity (MVPA) bout min per week, was measured via a sealed accelerometer and assessed on an intention-to-treat basis at 6 months (end of intervention) and 12 months (after a 6 month post-intervention follow-up period). Other outcome measures included steps, participants meeting 70 000 steps per week target, and health-related outcomes including weight, blood pressure, and quality-of-life measures. This trial is registered at ClinicalTrials.gov, number NCT01855776. FINDINGS: Between June 13, 2013, and Aug 15, 2014, 800 participants were recruited and randomly assigned to the control (n=201), Fitbit (n=203), charity (n=199), and cash (n=197) groups. At 6 months, compared with control, the cash group logged an additional 29 MVPA bout min per week (95% CI 10-47; p=0·0024) and the charity group an additional 21 MVPA bout min per week (2-39; p=0·0310); the difference between Fitbit only and control was not significant (16 MVPA bout min per week [-2 to 35; p=0·0854]). Increases in MVPA bout min per week in the cash and charity groups were not significantly greater than that of the Fitbit group. At 12 months, the Fitbit group logged an additional 37 MVPA bout min per week (19-56; p=0·0001) and the charity group an additional 32 MVPA bout min per week (12-51; p=0·0013) compared with control; the difference between cash and control was not significant (15 MVPA bout min per week [-5 to 34; p=0·1363]). A decrease in physical activity of -23 MVPA bout min per week (95% CI -42 to -4; p=0·0184) was seen when comparing the cash group with the Fitbit group. There were no improvements in any health outcomes (weight, blood pressure, etc) at either assessment. INTERPRETATION: The cash incentive was most effective at increasing MVPA bout min per week at 6 months, but this effect was not sustained 6 months after the incentives were discontinued. At 12 months, the activity tracker with or without charity incentives were effective at stemming the reduction in MVPA bout min per week seen in the control group, but we identified no evidence of improvements in health outcomes, either with or without incentives, calling into question the value of these devices for health promotion. Although other incentive strategies might generate greater increases in step activity and improvements in health outcomes, incentives would probably need to be in place long term to avoid any potential decrease in physical activity resulting from discontinuation. FUNDING: Ministry of Health, Singapore.

A Fit-Fat Index for Predicting Incident Diabetes in Apparently Healthy Men: A Prospective Cohort Study.

BACKGROUND: The purpose of this study was to examine the impact of combined cardiorespiratory fitness and waist-to-height ratio in the form of a fit-fat index on incident diabetes risk. Additionally, the independent predictive performance of cardiorespiratory fitness, waist-to-height ratio, and body mass index also were estimated and compared. METHODS: This was a prospective cohort study of 10,381 men who had a normal electrocardiogram and no history of major chronic disease at baseline from 1979 to 2005. Random survival forest models and traditional Cox proportional hazards models were used to predict diabetes at 5-, 10-, and 15-year incidence horizons. RESULTS: Overall, 4.8% of the participants developed diabetes. Receiver operating characteristic curve analyses for incidence risk demonstrated good discrimination using random survival forest models across fitness and fatness measures; Cox models were poor to fair. The differences between fitness and fatness measures across horizons were clinically negligible. Smoothed random survival forest estimates demonstrated the impact of each fitness and fatness measure on incident diabetes was intuitive and graded. CONCLUSIONS: Although fitness and fatness measures showed a similar discriminative ability in predicting incident diabetes, unique to the study was the ability of the fit-fat index to demonstrate a better indication of incident risk when compared to fitness or fatness alone. A single index combining cardiorespiratory fitness and waist-to-height ratio may be more useful because it can indicate improvements in either or both of the measures.