Project description:This study investigated the relationship between cardiorespiratory fitness (CRF) and adiposity in young adults.Data was collected from 133 students of a medical college of Pakistan. The study was conducted on young adults, aged 17-24 years, recruited from Jinnah Medical & Dental College, Karachi, between Aug-Dec, 2015. Queen's College Step Test was conducted to measure CRF and maximal oxygen uptake (VO2max) evaluated. Anthropometric measurements (body mass index, body fat, visceral fat, waist circumference) were taken to assess adiposity. Associations of VO2max and adiposity were analyzed.The prevalence of overweight/obesity was 44% overall. The VO2max (ml/kg/min) of males and females was 55.41±9.45 and 39.91±3.14, respectively, the gender difference being highly significant (p<0.001). Quartiles of VO2max showed strong inverse relationship between adiposity and VO2max, obese individuals having low VO2max (1st quartile) and normal weight individuals having high VO2max (4th quartile). VO2max correlated greatest with body fat in males (r = -0.600; p<0.001), and waist circumference in females (r = -0.319; p=0.004).The results indicate low CRF in young females and a strong inverse relationship between fitness levels and adiposity in young adults of both genders. Improving these parameters in our young population may prevent development of chronic non-communicable disease in later life.
Project description:ObjectiveWe aimed to assess the potential association of dietary (DIS) and lifestyle inflammation score (LIS) and their joint association (DLIS) with cardiorespiratory fitness (CRF) in Tehranian adults.DesignThe present study was designed cross-sectional.ParticipantsA total of 265 males and females aged 18-70 years (mean ± SD: 36.9 ± 13.3) were entered in the present cross-sectional study. Eligible participants were healthy men and women who were free of medications and had no acute or chronic infection or inflammatory disease.MeasuresThe DIS was calculated by the use of data from 18 anti- and pro-inflammatory dietary components, and the LIS by three non-dietary components including physical activity, smoking status, and general adiposity, with higher scores indicating a more pro-inflammatory diet and lifestyle, respectively. The DLIS was calculated by summing the DIS and LIS. CRF was assessed by the Bruce protocol and VO2 max was measuredas the main variable of CRF. The odds ratio (OR) and 95% confidence interval (CI) of CRF across tertiles of the DIS, LIS, and DLIS were estimated by logistic regression analysis with considering age, gender, energy intake, marital and education status, and occupation as confounders.ResultsThe DLIS ranged from -2.10 to 0.38 (mean ± SD: -1.25 ± 0.64). In the model that controlled for all variables, the ORs of CRF for the second and third tertiles of the DLIS as compared to the first tertile were 0.42 (95%CI: 0.20, 0.90) and 0.12 (95%CI: 0.05, 0.32), respectively (P-trend < 0.001). There was a strong inverse association between the LIS and CRF (ORthirdvs.firsttertile: 0.12, 95%CI: 0.05, 0.32). There was no association between DIS and CRF.ConclusionThe present study examined the joint association of inflammation-related lifestyle behaviors with CRF and found a strong inverse association between a pro-inflammatory lifestyle with CRF. We did not find any association between dietary inflammatory properties with CRF. Future studies should address the relationship between the inflammatory potential of the diet and CRF.
Project description:BackgroundThe interaction between cardiorespiratory fitness (CRF) and incidence of atrial fibrillation (AF) and the interaction between obesity and incidence of AF have been explored separately. Therefore, we evaluated the association between CRF, body mass index (BMI), and risk of developing AF in a cohort of middle-aged and older US Veterans.MethodsSymptom limited exercise tests (ETT) were conducted among 16,397 Veterans (97% male) from January 9,1987 to December 31,2017. No history of AF was evident at the time of the ETTs. CRF was expressed as quartiles of peak metabolic equivalents (METs) achieved within each age decile. Weight status was classified as normal (BMI < 25 kg/m2), overweight (BMI 25-30 kg/m2), obese (BMI 30-35 kg/m2), or severely obese (BMI > 35 kg/m2). Multivariable Cox proportional hazards regression models were used to compare the association between BMI, CRF categories, and incidence of AF.ResultsOver a median follow-up of 10.7 years, 2,155 (13.1%) developed AF. Obese and severely obese subjects had 13% and 32% higher risks for incidence of AF, respectively, vs. normal weight subjects. Overweight and obese subjects in the most fit quartile had 50% decline in AF risk compared to the least-fit subjects. Severely obese subjects had marked increases in AF risk (~50-60%) regardless of fitness level. Risk of developing AF increases with higher BMI and lower CRF.ConclusionImproving CRF should be advocated when assessing those at risk for developing AF.
Project description:BackgroundLittle is known regarding long-term consequences (≥5 years) of sport-related concussion (SRC) sustained during adolescence. Adolescent SRC has been linked to athlete considerations of sport participation and subsequent retirement from sport during this critical developmental period. Prolonged SRC symptoms can reduce ability to perform physical activity, and research suggests inactivity can extend years post-injury. Therefore, SRC may affect long-term physical activity, which may result in decreased cardiorespiratory fitness and increased adiposity.Objectives(1) To examine cardiorespiratory fitness, adiposity and associations with physical activity between three groups: adolescent SRC 5-15 years prior; adolescent musculoskeletal injury (MSK) 5-15 years prior; and individuals who played adolescent sport but were uninjured. (2) To explore whether biological sex-modified relationships assessed by the primary objective.MethodsYoung adults (16-33 years old) who sustained SRC (n = 54) or MSK (n = 52) during adolescent sport and uninjured individuals (n = 50) were recruited (n = 156) from previous Sport Injury Prevention Research Centre studies and word-of-mouth. Participants completed a cycle-ergometer maximal exertion test, dual-energy X-ray absorptiometry scanning, and wore actigraphs for 1-week post-testing. Outcome measures of cardiorespiratory fitness [peak oxygen consumption (VO2peak[ml/min])] and adiposity [fat mass index (FMI)] were examined in relation to cohort, sex, time since injury, lean mass index and moderate-to-vigorous physical activity [daily MVPA (min)] via multiple linear regression.ResultsIn relation to the uninjured cohort, MSK (mean difference = 297.14 ml/min; β = 2.88; 95%CI: 0.99-4.76, p = 0.003) and SRC (mean difference = 268.01 ml/min; β = 2.61; 95%CI: 0.77-4.44, p = 0.006) cohorts demonstrated higher VO2peak and this did not differ based on biological sex. FMI did not differ for MSK (mean difference= -0.10 kg/m2; β= -0.02; 95%CI: -0.22-0.18, p = 0.847) or SRC (mean difference=-0.22 kg/m2; β= -0.05; 95%CI: -0.24-0.15, p = 0.642) cohorts relative to the uninjured cohort for both males and females.ConclusionsIt is possible to maintain adequate long-term cardiorespiratory fitness and adiposity following adolescent SRC relative to those who only sustained sport related MSK injuries or did not sustain significant injuries as adolescents/adults.
Project description:Information on sex differences in the association between chronotype and depression is scarce. We aimed to investigate these differences using data from the Korea National Health and Nutrition Examination Survey in 2016. Chronotypes were categorised based on mid-sleep time on free days corrected by sleep debt accumulated on workdays (MSFsc): early type, < mean MSFsc - 1 standard deviation (SD); intermediate type, between mean MSFsc - 1 SD and MSFsc + 1 SD; and late type, > mean MSFsc + 1 SD. A Patient Health Questionnaire-9 score of ≥ 10 indicated depression. Among 5550 non-shift working adults aged 19-80 years, the prevalence rates of depression in the early, intermediate, and late chronotype groups were 7.4%, 4.5%, and 9.3%, respectively. Women with late chronotype (odds ratio [OR] = 2.9, 95% confidence interval [CI] = 1.8-4.7) showed a higher risk of depression than women with intermediate chronotype after adjusting for covariates. Women with early chronotype did not show a significant difference in depression risk (OR = 1.3, 95% CI = 0.9-2.0). In conclusion, late chronotype is associated with an increased risk of depression in women but not in men. Early chronotype is not associated with depression in women or men.
Project description:ObjectiveTo investigate whether the higher risks of certain cancers associated with high cardiorespiratory fitness can be explained by increased detection and unobserved confounders.DesignNationwide sibling-controlled cohort study of adolescents.SettingSweden.Participants1 124 049 men of which 477 453 were full siblings, who underwent mandatory military conscription examinations between 1972 and 1995 at a mean age of 18.3 years.Main outcome measuresHazard ratios (HR) and 95% confidence intervals (CI) of overall cancer diagnosis and cancer mortality, and 14 site-specific cancers (diagnosis or death), as recorded in the Swedish National Patient Register or Cause of Death Register until 31 December 2023, modelled using flexible parametric regressions.ResultsParticipants were followed until a median (maximum) age of 55.9 (73.5) years, during which 98 410 were diagnosed with cancer and 16 789 had a cancer-related death (41 293 and 6908 among full siblings respectively). The most common cancers were non-melanoma skin (27 105 diagnoses & 227 deaths) and prostate cancer (24 211 diagnoses & 869 deaths). In cohort analysis, those in the highest quartile of cardiorespiratory fitness had a higher risk of prostate (adjusted HR 1.10; 95% CI: 1.05 to 1.16) and skin cancer (e.g., non-melanoma HR 1.44; 1.37 to 1.50) compared to those in the lowest quartile, which led to a higher risk of any type of cancer diagnosis (HR 1.08; 1.06 to 1.11). However, those in the highest quartile had a lower risk of cancer mortality (HR 0.71; 0.67 to 0.76). When comparing full siblings, and thereby controlling for all behavioural, environmental, and genetic factors they share, the excess risk of prostate (HR 1.01; 0.90 to 1.13) and skin cancer (e.g., non-melanoma HR 1.09; 0.99 to 1.20) attenuated to the null. In contrast, the lower risk of overall cancer mortality was still statistically significant after control for such shared confounders (HR 0.78; 0.68 to 0.89). For other site-specific cancers, the influence of such confounding tended to vary, but none showed the same excess risk as prostate and non-melanoma skin cancer.ConclusionsThe association between high levels of adolescent cardiorespiratory fitness and excess risk of some cancers, such as prostate and non-melanoma skin cancer, appears to be fully explained by unobserved confounders shared between full siblings. However, the protective association with cancer mortality persists even after control for such confounding.
Project description:OBJECTIVE: Lower birth weight is associated with higher insulin resistance in later life. The aim of this study was to determine whether cardiorespiratory fitness modifies the association of birth weight with insulin resistance in adults. METHODS: The subjects were 379 Japanese individuals (137 males, 242 females) aged 20-64 years born after 1943. Insulin resistance was assessed using a homeostasis model assessment of insulin resistance (HOMA-IR), which is calculated from fasting blood glucose and insulin levels. Cardiorespiratory fitness (maximal oxygen uptake, VO2max) was assessed by a maximal graded exercise test on a cycle ergometer. Birth weight was reported according to the Maternal and Child Health Handbook records or the subject's or his/her mother's memory. RESULTS: The multiple linear regression analysis revealed that birth weight was inversely associated with HOMA-IR (β = -0.141, p = 0.003), even after adjustment for gender, age, current body mass index, mean blood pressure, triglycerides, HDL cholesterol, and smoking status. Further adjustments for VO2max made little difference in the relationship between birth weight and HOMA-IR (β = -0.148, p = 0.001), although VO2max (β = -0.376, p<0.001) was a stronger predictor of HOMA-IR than birth weight. CONCLUSIONS: The results showed that the association of lower birth weight with higher insulin resistance was little modified by cardiorespiratory fitness in adult life. However, cardiorespiratory fitness was found to be a stronger predictor of insulin resistance than was birth weight, suggesting that increasing cardiorespiratory fitness may have a much more important role in preventing insulin resistance than an individual's low birth weight.
Project description:Rigorously determined peak oxygen uptake is internationally recognized as the criterion measure of youth cardiorespiratory fitness. The assessment and interpretation of children's and adolescents' peak oxygen uptake and the relationship of the measure with other health-related variables are well documented. There has been a recent resurgence of interest in the prediction of peak oxygen uptake from field performance tests in young people. However, coupled with ratio-scaling of data and the raising of clinical red flags, these practices risk clouding our understanding of youth cardiorespiratory fitness and its relationship with current and future health. We believe these methods have the potential to mislead clinical practice and misguide recommendations for the promotion of youth cardiovascular health. We discuss relevant scientific evidence and interpretations that have emerged from predicting youth cardiorespiratory fitness from performance test scores. We argue that children deserve to have health care founded on evidence-based science and not on myths and misconceptions.
Project description:Background Substantial heterogeneity exists in the cardiorespiratory fitness (CRF) change in response to exercise training, and its long-term prognostic implication is not well understood. We evaluated the association between the short-term supervised training-related changes in CRF and CRF levels 10 years later. Methods and Results STRRIDE (Studies of a Targeted Risk Reduction Intervention Through Defined Exercise) trial participants who were originally randomized to exercise training for 8 months and participated in the 10-year follow-up visit were included. CRF levels were measured at baseline, after training (8 months), and at 10-year follow-up as peak oxygen uptake (vo2, mL/kg per min) using the maximal treadmill test. Participants were stratified into low, moderate, and high CRF response groups according to the training regimen-specific tertiles of CRF change. The study included 80 participants (age: 52 years; 35% female). At 10-year follow-up, the high-response CRF group had the least decline in CRF compared with the moderate- and low-response CRF groups (-0.35 versus -2.20 and -4.25 mL/kg per minute, respectively; P=0.02). This result was largely related to the differential age-related changes in peak oxygen pulse across the 3 groups (0.58, -0.23, and -0.86 mL/beat, respectively; P=0.03) with no difference in the peak heart rate change. In adjusted linear regression analysis, high response was significantly associated with greater CRF at follow-up independent of other baseline characteristics (high versus low [reference] CRF response: standard β=0.25; P=0.004). Conclusions Greater CRF improvement in response to short-term training is associated with higher CRF levels 10 years later. Lack of CRF improvements in response to short-term training may identify individuals at risk for exaggerated CRF decline with aging.
Project description:PurposeThis study was aimed to analyze the mediation role of cardiorespiratory fitness (CRF) on the association between fatness and cardiometabolic risk scores (CMRs) in European adolescents.MethodsA cross-sectional study was conducted in adolescents (n = 525; 46% boys; 14.1 ± 1.1 years old, mean ± SD) from 10 European cities involved in the Healthy Lifestyle in Europe by Nutrition in Adolescence study. CRF was measured by means of the shuttle run test, while fatness measures included body mass index (BMI), waist to height ratio, and fat mass index estimated from skinfold thicknesses. A clustered CMRs was computed by summing the standardized values of homeostasis model assessment, systolic blood pressure, triglycerides, total cholesterol/high-density lipoprotein cholesterol ratio, and leptin.ResultsLinear regression models indicated that CRF acted as an important and partial mediator in the association between fatness and CMRs in 12-17-year-old adolescents (for BMI: coefficients of the indirect role β = 0.058 (95% confidence interval (95%CI): 0.023-0.101), Sobel test z = 3.11 (10.0% mediation); for waist to height ratio: β = 4.279 (95%CI: 2.242-7.059), z =3.86 (11.5% mediation); and for fat mass index: β = 0.060 (95%CI: 0.020-0.106), z = 2.85 (9.4% mediation); all p < 0.01).ConclusionIn adolescents, the association between fatness and CMRs could be partially decreased with improvements to fitness levels; therefore, CRF contribution both in the clinical field and public health could be important to consider and promote in adolescents independently of their fatness levels.