Effects of an outdoor bicycle-based intervention in healthy rural Indian men with normal and low birth weight

Cycling in older adults: a scoping review

Introduction

Regular physical activity provides many health benefits to older adults. As a well-known form of physical activity, cycling can be an appropriate means for older people to meet WHO recommendations and to improve their health. In addition, cycling can help to protect the environment and reduce greenhouse gas emissions. The primary aim of this scoping review is to identify the currently available scientific evidence and gaps of research in this field.

Methods

A systematic search in seven databases resulted in 7,192 studies. After the exclusion of duplicates, studies were screened by two independent reviewers in a two-stage process. Based on previously defined inclusion criteria, 123 studies were included. Data extraction was based on a descriptive analytical method, and seven categories for the main topics of studies were developed. Data were extracted by three reviewers to analyze different characteristics of included articles such as age range, study design, data type, gender, type of bicycle, and country of origin.

Results

The included studies covered the following topics: (1) traffic safety, (2) cycling as physical activity or for transport, (3) health benefits, (4) environmental factors, (5) facilitators and barriers, (6) application of technology and (7) promotion of cycling. Results show that the majority of studies were performed in both younger (60-79 years) and older (80+ years) adults. Most studies had an observational study design, used conventional bicycles, and were based on quantitative methods. Researchers from the United States, Netherlands, and Japan published the highest number of studies related to cycling.

Discussion

Traffic safety was the most prevalent focus of the included studies. Gaps were identified with regard to studies focusing on the promotion of cycling, application of technology, as well as facilitators and barriers of cycling. While research on traffic safety should continue to be a high priority for public health, potentially more research should focus on how to get older people to bicycle more. This is warranted by the proven individual and planetary health benefits of cycling and the urgency of combating climate change.

Fitness Changes in Adolescent Girls Following In-School Combined Aerobic and Resistance Exercise: Interaction With Birthweight

PURPOSE

To assess the efficacy of a supervised in-school combined resistance and aerobic training program in adolescent girls and investigate whether responses differ according to birthweight.

METHODS

Participants (girls aged 13-17 y) were randomized either to an intervention replacing physical education (PE) classes with 2 × 60-minute training sessions per week (n = 58) or to a control group that continued to attend 2 × 60 minutes per week of curriculum PE (n = 41). We measured muscular fitness (handgrip, standing long jump, and sit-ups), cardiorespiratory fitness (20-m shuttle run), skinfolds, and lean body mass preintervention and postintervention and determined effect size (Hedge's g) differences between changes in these measures. We also compared changes within lower (<3000 g) and normal birthweight intervention and PE control subgroups.

RESULTS

The intervention group showed greater improvements in all the fitness measures and lean body mass (g = 0.22-0.48) and lower skinfold increases (g = 0.41) than PE controls. Within the intervention group, improvements in all fitness measures were larger in lower birthweight (g = 0.53-0.94) than in normal birthweight girls (g = 0.02-0.39).

CONCLUSION

Replacing curriculum PE with supervised training improved muscular and cardiorespiratory fitness and body composition outcomes in adolescent females. Our findings suggest an enhanced adaptive response to training in participants with lower birthweight which warrants further investigation.

Antenatal Steroid Exposure, Aerobic Fitness, and Physical Activity in Adolescents Born Preterm with Very Low Birth Weight

OBJECTIVE

To determine whether antenatal corticosteroid exposure is associated with aerobic fitness or physical activity participation in adolescents born preterm with very low birth weight (VLBW).

STUDY DESIGN

Observational cohort study of 14-year-old adolescents (n = 173) born with VLBW between 1992 and 1996 at a regional perinatal center with 91 exposed to antenatal corticosteroids. Aerobic fitness was determined from peak oxygen uptake (V˙O2peak) obtained via maximal exercise testing on a cycle ergometer. Physical activity levels for the past year and past 2 months were estimated from a questionnaire. Between-group comparisons for continuous variables were evaluated using independent t tests or Mann-Whitney U tests. Generalized linear models were used to compare differences in fitness and physical activity between those exposed to antenatal corticosteroids and not exposed to antenatal corticosteroids, with race and sex in models.

RESULTS

Regression analysis revealed an antenatal corticosteroids × sex × race interaction for V˙O2peak (P ≤ .001). Nonblack male adolescents exposed to antenatal corticosteroids had significantly greater V˙O2peak than nonblack male adolescents not exposed to antenatal corticosteroids expressed relative to body mass (mean difference [95% CI]; 8.5 [2.1-15.0] mL·kg-1·min-1) and lean body mass (9.0 [1.1-16.9] mL·kglean body mass-1·min-1). No antenatal corticosteroid group differences in V˙O2peak were evident in black male adolescents, or black and nonblack female adolescents. Male adolescents exposed to antenatal corticosteroids reported participating in significantly more total physical activity (medians: 14.6 vs 8.5) and vigorous physical activity (3.0 vs 0.95) per week for the past 2 months than male adolescents not exposed to antenatal corticosteroids.

CONCLUSIONS

Exposure to antenatal corticosteroids was associated with greater physical activity participation and aerobic fitness in adolescents with VLBW, particularly in nonblack male adolescents, which may confer health benefits in this at-risk population.

Changes in Cycling and Incidence of Overweight and Obesity among Danish Men and Women

PURPOSE

Overweight and obesity are associated with increased risk of several noncommunicable diseases and are a growing public health issue. The primary purpose of the current study was to investigate incidence of overweight and obesity according to 5-yr cycling habits. The secondary purpose was to investigate incidence of remission from overweight and obesity according to 5-yr cycling habits.

METHODS

We analyzed 9014 men and 8661 women without chronic disease who between 1993 and 2003 completed two assessments approximately 5 yr apart. At both assessments, participants reported habitual cycling habits. Also, body weight and waist circumference were measured by a laboratory technician at baseline and self-assessed at second examination. We computed multivariable adjusted odds ratios (OR) with 95% confidence intervals (CI) for development of and remission from abdominal and general overweight and obesity, according to 5-yr cycling habits.

RESULTS

Continued cycling was associated with lower odds for incidence of abdominal (men, >102 cm; women, >88 cm) and incidence of general (body mass index ≥30 kg·m) obesity; compared with no cycling, OR (95% CI) values were 0.82 (0.74-0.91) and 0.74 (0.60-0.92) for abdominal and general obesity, respectively. Also, those who initiated cycling had lower odds for incidence of abdominal obesity; OR (95% CI) was 0.85 (0.73-1.00) relative to no cycling. Although we found no evidence of remission from abdominal and general overweight and obesity according to 5-yr cycling habits, those who continued cycling had significantly larger decreases in waist circumference relative to noncyclists (β coefficient (95% CI), -0.95 cm (-1.56 to -0.33 cm)).

CONCLUSIONS

Continued cycling compared with no cycling was associated with lower odds for abdominal and general obesity. Also, late-in-life initiation of cycling was associated with lower odds for abdominal obesity relative to no cycling.

Is willingness to exercise programmed in utero? Reviewing sedentary behavior and the benefits of physical activity in intrauterine growth restricted individuals

OBJECTIVE

The literature suggests that a fetus will adapt to surrounding adversities by optimizing its use of energy to improve survival, ultimately leading to the programming of the individual's energy intake and expenditure. While recent reviews focused on the fetal programming of energy intake and food preferences, there is also some evidence that fetal adversity is associated with diminished physical activity levels. Therefore, we aimed to review (a) the evidence for an association between being born with intrauterine growth restriction and sedentarism over the life-course and (b) the potential benefits of physical activity over cardiometabolic risk factors for this population.

SOURCES

PubMed, Scielo, Scopus and Embase.

SUMMARY OF FINDINGS

Most clinical studies that used objective measures found no association between intrauterine growth restriction and physical activity levels, while most studies that used self-reported questionnaires revealed such relationships, particularly leisure time physical activity. Experimental studies support the existence of fetal programming of physical activity, and show that exposure to exercise during IUGR individuals' life improves metabolic outcomes but less effect was seen on muscle architecture or function.

CONCLUSIONS

Alterations in muscle strength and metabolism, as well as altered aerobic performance, may predispose IUGR individuals to be spontaneously less physically active, suggesting that this population may be an important target for preventive interventions. Although very heterogeneous, the different studies allow us to infer that physical activity may have beneficial effects especially for individuals that are more vulnerable to metabolic modifications such as those with IUGR.

Dietary and physical activity recommendations to prevent type 2 diabetes in South Asian adults: A systematic review

Intervention trials and guidelines for the prevention of type 2 diabetes (T2D) in populations of South Asian origin often include strategies to improve diet and physical activity that are based on those developed for other populations. These may be suboptimal for the South Asian target populations. We aimed to provide an overview of included recommended dietary and physical activity components, and to identify whether these were supported by evidence of their effectiveness. Databases were searched until September 2017 for intervention studies and guidelines with an adult South Asian population without T2D. The protocol was registered in PROSPERO, registration number: CRD42015207067. The quality of included studies and guidelines was assessed. Dietary and physical activity components, and effects on T2D incidence, glycemic status and adiposity measures, were summarized in tabular format and evaluated narratively. Eighteen intervention studies and four guidelines were identified. Dietary and physical activity components were similar to recommendations for the general population. Intervention studies and guidelines did not reference evidence to support the effectiveness of components included in the intervention for South Asian populations in particular. Moreover, we were unable to assess patterns of components to determine the effects of specific components. Evaluation of current and emerging components among South Asian populations and subgroups seems necessary to formulate more specific recommendations in future intervention studies and guidelines.

Associations between Recreational and Commuter Cycling, Changes in Cycling, and Type 2 Diabetes Risk: A Cohort Study of Danish Men and Women

BACKGROUND

Cycling is a recreational activity and mode of commuting with substantial potential to improve public health in many countries around the world. The aim of this study was to examine prospective associations between recreational and commuter cycling, changes in cycling habits, and risk of type 2 diabetes (T2D) in Danish adults from the Diet, Cancer and Health cohort study.

METHODS AND FINDINGS

At baseline from 1993 to 1997, 24,623 men and 27,890 women from Denmark, 50-65 y of age and free of T2D and other chronic diseases, underwent a number of assessments, including completing a lifestyle questionnaire also addressing cycling habits. Approximately 5 y later, at a second examination, participants completed a new, updated lifestyle questionnaire. Cox regression was used to estimate hazard ratios (HRs) of incident T2D registered in the Danish National Diabetes Registry, according to recreational and commuter cycling and changes in cycling habits, with adjustment for a priori known T2D risk factors. During 743,245.4 person-years of follow-up (mean follow-up 14.2 y), 6,779 incident cases of T2D were documented. Multivariable adjusted HRs (95% confidence interval [CI]) were 1, 0.87 (0.82, 0.93), 0.83 (0.77, 0.89), 0.80 (0.74, 0.86) and 0.80 (0.74, 0.87) (p for trend = <0.001) for 0, 1-60, 61-150, 151-300, and >300 min/wk of total cycling (recreational and commuter cycling), respectively. In analysis of seasonal cycling, multivariable adjusted HRs (95% CI) were 1, 0.88 (0.83, 0.94), and 0.80 (0.76, 0.85) for non-cyclists, seasonal cyclists (those cycling only in summer or winter), and those cycling during both summer and winter, respectively. How changes in total cycling from baseline to the second examination affected risk was also investigated, and multivariable adjusted HRs (95% CI) were 1, 0.88 (0.78, 1.01), 0.80 (0.69, 0.91), and 0.71 (0.65, 0.77) for non-cyclists and for those who ceased, initiated, or continued cycling between baseline and the second examination, respectively. Lastly, in the analysis of commuter cycling, multivariable HRs (95% CI) were 1, 0.72 (0.60, 0.87), 0.83 (0.69, 1.00), and 0.70 (0.57, 0.85) (p for trend = <0.001) for cycling 0, 1-60, 61-150, and >150 min/wk to work, respectively. The main limitation of the current study is the use of self-reported physical activity.

CONCLUSIONS

Commuter and recreational cycling was consistently associated with lower risk of T2D in Danish adults. Our results also provide evidence that late-in-life initiation of or continued engagement in cycling lowers risk of T2D.

Are hepatic and soleus lipid content, assessed by magnetic resonance spectroscopy, associated with low birth weight or insulin resistance in a rural Indian population of healthy young men?

AIMS

To assess young healthy men from rural India, who had normal or low birth weights, using magnetic resonance spectroscopy to determine the potential differences in ectopic fat storage between birth weight groups, and to determine if ectopic fat storage was associated with insulin resistance in this population.

METHODS

A total of 54 lean men with normal birth weight and 49 lean men with low birth weight (age range 18-22 years) from rural India were recruited. All the men underwent anthropometry, magnetic resonance spectroscopy, a hyperinsulinaemic-euglycaemic clamp and a dual-energy X-ray absorptiometry.

RESULTS

The median (interquartile range) values for hepatic cellular lipids, intramyocellular lipids and extramyocellular lipids, measured using magnetic resonance spectroscopy were 0.76 (0.1-1.8)%, 1.27 (1.0-2.3)% and 1.89 (1.3-3.2)%, respectively, for the normal birth weight group and 0.4 (0.1-1.3)%, 1.38 (0.9-2.2)% and 2.07 (1.2-2.8)%, respectively, for the low birth weight group (P > 0.05). No difference in ectopic fat storage was observed between the low and normal birth weight groups, with or without adjustment for age and total fat percentage. Homeostatic model assessment of insulin resistance values were not associated with hepatic cellular, intramyocellular or extramyocellular lipid content in any of the groups. Total fat percentage was the only independent predictor of intramyocellular and extramyocellular lipid content.

CONCLUSION

Young and lean men from rural India with low birth weight were not observed to have ectopic fat storage in the liver or muscle, and the amount of liver and muscle fat was unrelated to insulin resistance. Older age and/or an urban affluent lifestyle may be required to show a potential role of ectopic fat storage on insulin resistance in Indian people with low or normal birth weight.

From fatalism to mitigation: A conceptual framework for mitigating fetal programming of chronic disease by maternal obesity

Prenatal development is recognized as a critical period in the etiology of obesity and cardiometabolic disease. Potential strategies to reduce maternal obesity-induced risk later in life have been largely overlooked. In this paper, we first propose a conceptual framework for the role of public health and preventive medicine in mitigating the effects of fetal programming. Second, we review a small but growing body of research (through August 2015) that examines interactive effects of maternal obesity and two public health foci - diet and physical activity - in the offspring. Results of the review support the hypothesis that diet and physical activity after early life can attenuate disease susceptibility induced by maternal obesity, but human evidence is scant. Based on the review, we identify major gaps relevant for prevention research, such as characterizing the type and dose response of dietary and physical activity exposures that modify the adverse effects of maternal obesity in the offspring. Third, we discuss potential implications of interactions between maternal obesity and postnatal dietary and physical activity exposures for interventions to mitigate maternal obesity-induced risk among children. Our conceptual framework, evidence review, and future research directions offer a platform to develop, test, and implement fetal programming mitigation strategies for the current and future generations of children.