Background Non-exercise estimated cardiorespiratory fitness(NEE-CRF)has been shown to be associated with mortality,although its association with cancer incidence is unknown.The study aimed to assess the prospective as...Background Non-exercise estimated cardiorespiratory fitness(NEE-CRF)has been shown to be associated with mortality,although its association with cancer incidence is unknown.The study aimed to assess the prospective association between NEE-CRF and cancer incidence in a large cohort of men and women.Methods The National Institutes of Health-American Association of Retired Persons diet and health study is a prospective cohort that included 402,548 participants aged 50–71 years who were free from cancer at baseline(1995–1996)(men(n=238,835)and women(n=163,713))and were followed until December 31,2015.The exposure variable was NEE-CRF expressed in metabolic equivalents.NEE-CRF was estimated using a validated equation of self-reported predictors on demographics and lifestyle behaviors derived from baseline questionnaires.Primary outcomes were total cancer incidence and incidence of prostate,breast,lung,and colorectal cancers.Cox proportional hazards models were analyzed for the association between NEE-CRF and cancer incidence outcomes adjusted for established cancer risk factors.Results During 13.7±3.2 years of follow-up(mean±SD),64,344 men and 31,315 women developed a new cancer.For every 1-metabolic equivalent higher NEE-CRF,the hazard ratios and 95%confidence intervals(95%CIs)were 0.96(95%CI:0.94–0.97)and 0.88(95%CI:0.84–0.92)of total and colorectal cancer incidence among men,and 0.95(95%CI:0.93–0.97)and 0.94(95%CI:0.91–0.97)of total and breast cancer incidence among women,respectively(all p<0.001).NEE-CRF was not associated with incidence of prostate and lung cancers in men or colorectal and lung cancers in women.Conclusion These results suggest that higher CRF levels,as assessed by the applied non-exercise estimated method,may provide preventive benefits against the development of cancer,while low CRF could potentially serve as a modifiable cancer risk factor.Integrating NEE-CRF into screening paradigms and referring low-fit individuals to improve CRF could complement the public health prevention strategy against cancer.展开更多
Background:Intensive exercise changes physiological need for glucose and several biochemical pathways responsible for its metabolism response.Among them are those which involve insulin,insulin-like growth factor(IGF-1...Background:Intensive exercise changes physiological need for glucose and several biochemical pathways responsible for its metabolism response.Among them are those which involve insulin,insulin-like growth factor(IGF-1),and IGF-binding proteins(IGFBPs).Different types and degrees of exercise,as well as an athlete's fitness,may induce a range of responses regarding concentrations and time needed for the alteration.The idea of the work was to find out whether and how insulin/IGF axis responds to additional physical activity in the already trained subjects and if so,is the adaptation potentially beneficial from the aspect of metabolic control.Methods:The effect of 4-week intensive training on campus(preparatory training) on the levels of insulin,IGF-1,and IGFBPs during maximal progressive exercise test(MPET) on a treadmill was compared to the results obtained during MPET conducted after a regular training season of a female elite handball team(n = 17,age:17 ± 1 years,height:171 ± 8 cm,weight:65 ± 8 kg,body mass index:22 ± 1 kg/m^2 at the beginning of the study;there were no significant changes at the end).Serum samples were obtained from players immediately before the test(basal),at the end of the test after reaching the point of maximal oxygen consumption(VO_(2max)),and after recovery.Results:The concentration of insulin decreased at VO_(2max),but remained higher in players after preparatory training(12.2 ± 2.5 m U/L vs.8.9 ± 4.4 m U/L,p = 0.049).The level of IGFBP-1 decreased in players at VO_(2max) in either case of training,but it remained much higher in tests performed after the preparatory regime than before(p = 0.029).Concentrations of IGF-1,IGFBP-2,-3,and-4 did not change significantly.Conclusion:The inverse relation between insulin and IGFBP-1 was lost during MPET,as these 2 molecules changed in the same direction.The results obtained suggest less severe stress-induced depression of insulin and IGFBP-1 after preparatory training.But another metabolic mechanism cannot be excluded,and that is potentially impaired insulin sensitivity resulting in higher level of IGFBP-1.展开更多
基金supported (in part) by the Intramural Research Program of the NIH,National Cancer Institute
文摘Background Non-exercise estimated cardiorespiratory fitness(NEE-CRF)has been shown to be associated with mortality,although its association with cancer incidence is unknown.The study aimed to assess the prospective association between NEE-CRF and cancer incidence in a large cohort of men and women.Methods The National Institutes of Health-American Association of Retired Persons diet and health study is a prospective cohort that included 402,548 participants aged 50–71 years who were free from cancer at baseline(1995–1996)(men(n=238,835)and women(n=163,713))and were followed until December 31,2015.The exposure variable was NEE-CRF expressed in metabolic equivalents.NEE-CRF was estimated using a validated equation of self-reported predictors on demographics and lifestyle behaviors derived from baseline questionnaires.Primary outcomes were total cancer incidence and incidence of prostate,breast,lung,and colorectal cancers.Cox proportional hazards models were analyzed for the association between NEE-CRF and cancer incidence outcomes adjusted for established cancer risk factors.Results During 13.7±3.2 years of follow-up(mean±SD),64,344 men and 31,315 women developed a new cancer.For every 1-metabolic equivalent higher NEE-CRF,the hazard ratios and 95%confidence intervals(95%CIs)were 0.96(95%CI:0.94–0.97)and 0.88(95%CI:0.84–0.92)of total and colorectal cancer incidence among men,and 0.95(95%CI:0.93–0.97)and 0.94(95%CI:0.91–0.97)of total and breast cancer incidence among women,respectively(all p<0.001).NEE-CRF was not associated with incidence of prostate and lung cancers in men or colorectal and lung cancers in women.Conclusion These results suggest that higher CRF levels,as assessed by the applied non-exercise estimated method,may provide preventive benefits against the development of cancer,while low CRF could potentially serve as a modifiable cancer risk factor.Integrating NEE-CRF into screening paradigms and referring low-fit individuals to improve CRF could complement the public health prevention strategy against cancer.
基金supported by the Ministry of Education,Science and Technological Development of the Republic of Serbia(No.173042 and III41030)
文摘Background:Intensive exercise changes physiological need for glucose and several biochemical pathways responsible for its metabolism response.Among them are those which involve insulin,insulin-like growth factor(IGF-1),and IGF-binding proteins(IGFBPs).Different types and degrees of exercise,as well as an athlete's fitness,may induce a range of responses regarding concentrations and time needed for the alteration.The idea of the work was to find out whether and how insulin/IGF axis responds to additional physical activity in the already trained subjects and if so,is the adaptation potentially beneficial from the aspect of metabolic control.Methods:The effect of 4-week intensive training on campus(preparatory training) on the levels of insulin,IGF-1,and IGFBPs during maximal progressive exercise test(MPET) on a treadmill was compared to the results obtained during MPET conducted after a regular training season of a female elite handball team(n = 17,age:17 ± 1 years,height:171 ± 8 cm,weight:65 ± 8 kg,body mass index:22 ± 1 kg/m^2 at the beginning of the study;there were no significant changes at the end).Serum samples were obtained from players immediately before the test(basal),at the end of the test after reaching the point of maximal oxygen consumption(VO_(2max)),and after recovery.Results:The concentration of insulin decreased at VO_(2max),but remained higher in players after preparatory training(12.2 ± 2.5 m U/L vs.8.9 ± 4.4 m U/L,p = 0.049).The level of IGFBP-1 decreased in players at VO_(2max) in either case of training,but it remained much higher in tests performed after the preparatory regime than before(p = 0.029).Concentrations of IGF-1,IGFBP-2,-3,and-4 did not change significantly.Conclusion:The inverse relation between insulin and IGFBP-1 was lost during MPET,as these 2 molecules changed in the same direction.The results obtained suggest less severe stress-induced depression of insulin and IGFBP-1 after preparatory training.But another metabolic mechanism cannot be excluded,and that is potentially impaired insulin sensitivity resulting in higher level of IGFBP-1.
