Objective: To provide a broad overview of the state of physical activity (PA) research in the form of (1) definitions of PA, (2) health benefits, (3) prevalence, (4) correlates and (5) interventions.
...Design: A high-level overview of published reviews of the literature.
Results: Regular PA is an effective primary and secondary preventative strategy against at least 25 chronic medical conditions with risk reduction typically in the 20-30% range. While approximately 75% of adults meet recommended PA guidelines, the prevalence is slightly lower for women compared to men, and considerably lower for youth, older adults and those in higher income countries. Motivation, self-efficacy and self-regulation remain consistent correlates of PA. Interventions show PA changes in the small effect size range for adults and youth but the heterogeneity is considerable across studies. Only a few (aggregate of behavioural regulation strategies, supervision, high frequency of contact) reliable moderators of intervention success were identified across study quality, sample characteristics, theory/behaviour change techniques and delivery modes/settings.
Conclusion: PA research should continue to examine the mechanisms causing health outcomes, the dose that can lead to clinically relevant changes in health status, the scope and validity of PA surveillance and innovative behaviour change techniques, while improving the reach and duration of PA interventions.
Abstract The health benefits of regular physical activity are irrefutable; virtually everyone can benefit from being active. The evidence is overwhelming with risk reductions of at least 20%-30% for ...more than 25 chronic medical conditions and premature mortality. Even higher risk reductions (ie, ≥ 50%) are observed when objective measures of physical fitness are taken. International physical activity guidelines generally recommend 150 minutes per week of moderate- to vigorous-intensity physical activity. A critical review of the literature indicates that half of this volume of physical activity might lead to marked health benefits. There is compelling evidence to support health promotion strategies that emphasize that health benefits can be accrued at a lower volume and/or intensity of physical activity. Public health policies are needed that reduce the barriers to physical activity participation such that everyone can reap the benefits of physical activity. It is also important to highlight that sedentary time (particularly sitting time) carries independent health risks. The simple message of “move more and sit less” likely is more understandable by contemporary society and is formed on the basis of a strong body of evidence. For practitioners who work directly with clients, it is recommended that an individualized prescription (dosage) that takes into consideration the unique characteristics and needs of the client is provided. Physical activity or exercise promotion should not be done in isolation; it should be part of an integrated approach to enhance healthy lifestyle behaviours.
The health benefits of physical activity and exercise are clear; virtually everyone can benefit from becoming more physically active. Most international guidelines recommend a goal of 150 min/week of ...moderate-to-vigorous intensity physical activity. Many agencies have translated these recommendations to indicate that this volume of activity is the minimum required for health benefits. However, recent evidence has challenged this threshold-centered messaging as it may not be evidence-based and may create an unnecessary barrier to those who might benefit greatly from simply becoming more active. This systematic review evaluates recent systematic reviews that have examined the relationship between physical activity and health status.
Systematic reviews and/or meta-analyses (based largely on epidemiological studies consisting of large cohorts) have demonstrated a dose-response relationship between physical activity and premature mortality and the primary and secondary prevention of several chronic medical conditions. The relationships between physical activity and health outcomes are generally curvilinear such that marked health benefits are observed with relatively minor volumes of physical activity.
These findings challenge current threshold-based messaging related to physical activity and health. They emphasize that clinically relevant health benefits can be accrued by simply becoming more physically active. VIDEO ABSTRACT: http://links.lww.com/HCO/A42.
This systematic review examines critically the scientific basis for Canada's Physical Activity Guide for Healthy Active Living for adults. Particular reference is given to the dose-response ...relationship between physical activity and premature all-cause mortality and seven chronic diseases (cardiovascular disease, stroke, hypertension, colon cancer, breast cancer, type 2 diabetes (diabetes mellitus) and osteoporosis). The strength of the relationship between physical activity and specific health outcomes is evaluated critically. Literature was obtained through searching electronic databases (e.g., MEDLINE, EMBASE), cross-referencing, and through the authors' knowledge of the area. For inclusion in our systematic review articles must have at least 3 levels of physical activity and the concomitant risk for each chronic disease. The quality of included studies was appraised using a modified Downs and Black tool. Through this search we identified a total of 254 articles that met the eligibility criteria related to premature all-cause mortality (N = 70), cardiovascular disease (N = 49), stroke (N = 25), hypertension (N = 12), colon cancer (N = 33), breast cancer (N = 43), type 2 diabetes (N = 20), and osteoporosis (N = 2). Overall, the current literature supports clearly the dose-response relationship between physical activity and the seven chronic conditions identified. Moreover, higher levels of physical activity reduce the risk for premature all-cause mortality. The current Canadian guidelines appear to be appropriate to reduce the risk for the seven chronic conditions identified above and all-cause mortality.
To describe physical activity (PA) intensity across a school day and assess the percentage of girls and boys achieving recommended guidelines.
The authors measured PA via accelerometry in 380 ...children (8-11 years) and examined data representing (1) the whole school day, (2) regular class time, (3) recess, (4) lunch and (5) scheduled physical education (PE). Activity was categorised as sedentary (SED), light physical activity (LPA) or moderate to vigorous physical activity (MVPA) using age-specific thresholds. They examined sex differences across PA intensities during each time period and compliance with recommended guidelines.
Girls accumulated less MVPA and more SED than boys throughout the school day (MVPA -10.6 min; SED +13.9 min) recess (MVPA -1.6 min; SED +1.7 min) and lunch (MVPA -3.1 min; SED +2.9 min). Girls accumulated less MVPA (-6.2 min), less LPA (-2.5 min) and more SED (+9.4 min) than boys during regular class time. Fewer girls than boys achieved PA guidelines during school (90.9% vs 96.2%), recess (15.7% vs 34.1%) and lunch (16.7% vs 37.4%). During PE, only 1.8% of girls and 2.9% of boys achieved the PA guidelines. Girls and boys accumulated similar amounts of MVPA, LPA and SED.
The MVPA deficit in girls was due to their sedentary behaviour as opposed to LPA. Physical activity strategies that target girls are essential to overcome this deficit. Only a very small percentage of children met physical activity guidelines during PE. There is a great need for additional training and emphasis on PA during PE. In addition schools should complement PE with PA models that increase PA opportunities across the school day.
Introduction
The health benefits of exercise are well established. However, the relationship between exercise volume and intensity and health benefits remains unclear, particularly the benefits of ...low-volume and intensity exercise.
Purpose
The primary purpose of this investigation was, therefore, to examine the dose–response relationship between exercise volume and intensity with derived health benefits including volumes and intensity of activity well below international recommendations.
Methods
Generally healthy, active participants (
n
= 72; age = 44 ± 13 years) were assigned randomly to control (
n
= 10) or one of five 13-week exercise programs: (1) 10-min brisk walking 1×/week (
n
= 10), (2) 10-min brisk walking 3×/week (
n
= 10), (3) 30-min brisk walking 3×/week (
n
= 18), (4) 60-min brisk walking 3×/week (
n
= 10), and (5) 30-min running 3×/week (
n
= 14), in addition to their regular physical activity. Health measures evaluated pre- and post-training including blood pressure, body composition, fasting lipids and glucose, and maximal aerobic power (VO
2
max).
Results
Health improvements were observed among programs at least 30 min in duration, including body composition and VO
2
max: 30-min walking 28.8–34.5 mL kg
−1
min
−1
, 60-min walking 25.1–28.9 mL kg
−1
min
−1
, and 30-min running 32.4–36.4 mL kg
−1
min
−1
. The greater intensity running program also demonstrated improvements in triglycerides.
Conclusion
In healthy active individuals, a physical activity program of at least 30 min in duration for three sessions/per week is associated with consistent improvements in health status.
Type 1 diabetes mellitus (T1DM) is associated with an increased risk for cardiovascular disease (CVD) related morbidity and premature mortality. Regular physical activity plays an important role in ...the primary and secondary prevention of CVD, improving overall health and wellbeing. Previous observational studies have examined the associations between self-reported physical activity and CVD risk factors in largely adult Caucasian populations. However, limited work has evaluated the relationship between objectively measured physical activity and CVD risk factors in other ethnicities, particularly Chinese youth living with T1DM.
This cross-sectional study assessed CVD risk factors, physical activity, and aerobic fitness (and their associations) in Chinese youth living with T1DM (n = 48) and peers (n = 19) without T1DM. Primary outcomes included blood pressure, lipid profiles, and physical activity (accelerometry). Statistical differences between groups were determined with chi-square, independent-samples t-tests, or analysis of covariance. The associations between aerobic fitness, daily physical activity variables, and CVD risk factors were assessed with univariate and multivariate linear regression analyses.
Results were summarized using means and standard deviation (SD) for normally distributed variables and medians and 25-75th quartile for non-normally distributed variables. In comparison to peers without diabetes, youth living with T1DM showed higher levels of total cholesterol (3.14 ± 0.67 vs. 4.03 ± 0.81 mmol·L
, p = 0.001), low-density lipoprotein cholesterol (1.74 ± 0.38 vs. 2.31 ± 0.72 mmol·L
, p = 0.005), and triglycerides (0.60 ± 0.40 vs. 0.89 ± 0.31 mmol·L
p = 0.012), and lower maximal oxygen power (44.43 ± 8.29 vs. 35.48 ± 8.72 mL·kg
·min
, p = 0.003), total physical activity counts (451.01 ± 133.52 vs. 346.87 ± 101.97 counts·min
, p = 0.004), metabolic equivalents (METs) (2.41 ± 0.60 vs. 2.09 ± 0.41 METs, p = 0.033), moderate-to-vigorous intensity physical activity MVPA: 89.57 (61.00-124.14) vs (53.19 (35.68-63.16) min, p = 0.001, and the percentage of time spent in MVPA 11.91 (7.74-16.22) vs 8.56 (6.18-10.12) %, p = 0.038. The level of high-density lipoprotein cholesterol was positively associated with METs (β = 0.29, p = 0.030, model R
= 0.168), and the level of triglycerides was negatively associated with physical activity counts (β = - 0.001, p = 0.018, model R
= 0.205) and METs (β = - 0.359, p = 0.015, model R
= 0.208), and positively associated with time spent in sedentary behaviour (β = 0.002, p = 0.041, model R
= 0.156) in persons living with T1DM.
Chinese youth with T1DM, despite their young age and short duration of diabetes, present early signs of CVD risk, as well as low physical activity levels and cardiorespiratory fitness compared to apparently healthy peers without diabetes. Regular physical activity is associated with a beneficial cardiovascular profile in T1DM, including improvements in lipid profile. Thus, physical activity participation should be widely promoted in youth living with T1DM.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Purpose
To understand the association between heart rate variability and indices of fatigue, total sleep time, and reaction time in shift workers.
Methods
Ten participants from the British Columbia ...Wildfire Service management team were examined over a 14-day active fire-line period. Daily measures of subjective fatigue, sleepiness, and alertness were recorded using a visual analog scale. Daily total sleep time was recorded using a wrist actigraph. Cardiac autonomic modulation was examined each morning using heart rate variability (HRV). Three measures of reaction time (simple reaction time, choice reaction tie, and discriminatory reaction time) was examined on days 1, 5, 10, and 14. Multiple linear regression analysis was utilized to examine the association between HRV and indices of fatigue, total sleep time, and reaction time.
Results
Mean shift duration was 13.8 ± 0.77 h. Significant inverse associations were observed between HRV and sleepiness
r
= − 0.60,
p
= 0.000 and fatigue
r
= − 0.55,
p
= 0.000, and a positive association with total sleep time (min)
r
= 0.28,
p
= 0.009. There were no significant relationships between HRV and simple reaction time (ms)
r
= − 0.32,
p
= 0.182, choice reaction time (ms)
r
= − 0.10,
p
= 0.850, or discriminatory reaction time (ms)
r
= − 0.09,
p
= 0.881.
Conclusions
HRV displayed significant associations with indices of fatigue and sleep, whereby demonstrating its utility as a practical tool for monitoring the development of fatigue in wildland firefighters and for providing insight when to make lifestyle modifications to preserve alertness.
Our special series on Cardiac Rehabilitation outlined the importance of routine physical activity and/or exercise participation in the primary and secondary prevention of cardiovascular disease and ...many other chronic medical conditions. The evidence is overwhelming, demonstrating that nearly everyone can benefit from becoming more physically active. This messaging has been widely disseminated at regional, national, and international levels. Often, this messaging highlights a physical inactivity crisis and the health perils of not engaging in sufficient amounts of physical activity. This deficits-based messaging often includes generic threshold-based recommendations stating that health benefits can only be accrued with specific volumes or intensities of physical activity. In this Editorial, we argue that the current generic and deficits-based messaging misses a great opportunity to focus on the positive and to facilitate hope and real change at the individual, community, and population levels. We advocate a strengths-based approach to health and wellness promotion that focuses on the innate strengths of individuals, families, and communities to enable self-empowerment and self-determination related to health and wellness. By taking a strengths-based approach, we can build hope, promoting the positive aspects of routine physical activity and exercise participation and providing a greater opportunity to enhance health and wellbeing for everyone.
Indigenous populations currently experience greater cardiovascular disease burdens. However, subclinical vascular structure and function among these populations is not well known. This investigation ...evaluated vascular structure and function among Canadian Indigenous populations. Blood pressure, body composition, pulse-wave velocity (PWV), baroreceptor sensitivity (BRS), arterial compliance and intima-media thickness (IMT) were measured. Vascular measures were evaluated across sexes and age groups. Vascular assessments were conducted among 55 Indigenous adults (38±18 years, 29 Female), including both First Nations (N=36) and Métis (N=19) individuals. Some differences in vascular measures were found between males and females, respectively (spectral BRS: 9.6±6.8 ms mm Hg(-1) vs 16.9±10.0 ms mm Hg(-1), P=0.01; small arterial compliance: 8.9±3.7 ml mm Hg(-1) × 100 vs 6.4±2.3 ml mm Hg(-1) × 100, P=0.004), with similar measures of overall IMT (0.61±0.14 mm vs 0.57±0.08 mm, P=0.19) and central PWV (5.7±2.5 m s(-1) vs 5.1±2.3 m s(-1), P=0.58). Greater IMT, and lower BRS and arterial compliance were identified among older adults. This relatively healthy population demonstrated healthy vascular measures, with poorer measures among older individuals.
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