Interrupting long periods of sitting: good STUFF

Geert M Rutten^1*, Hans H Savelberg², Stuart JH Biddle³ and Stef PJ Kremers¹

Abstract

There is increasing evidence that sedentary behaviour is in itself a health risk, regardless of the daily amount of moderate to vigorous physical activity. Therefore, sedentary behaviour should be targeted as important health behaviour.

It is known that even relatively small changes of health behaviour often require serious efforts from an individual and from people in their environment to become part of their lifestyle. Therefore, interventions to promote healthy behaviours should ideally be simple, easy to perform and easily available. Since sitting is likely to be highly habitual, confrontation with an intervention should almost automatically elicit a reaction of getting up, and thus break up and reduce sitting time. One important prerequisite for successful dissemination of such an intervention could be the use of a recognisable term relating to sedentary behaviour, which should have the characteristics of an effective brand name. To become wide spread, this term may need to meet three criteria: the “Law of the few”, the “Stickiness factor”, and the “Power of context”. For that purpose we introduce STUFF: Stand Up For Fitness. STUFF can be defined as “interrupting long sitting periods by short breaks”, for instance, interrupting sitting every 30 min by standing for at least five minutes.

Even though we still need evidence to test the health-enhancing effects of interrupted sitting, we hope that the introduction of STUFF will facilitate the testing of the social, psychological and health effects of interventions to reduce sitting time.

Keywords: 

Sedentary behavior; Physical activity; Sitting time reduction; Health promotion; Dissemination


http://www.ijbnpa.org/content/10/1/1

Myths, Presumptions, and Facts about Obesity

Krista Casazza, Ph.D., R.D., Kevin R. Fontaine, Ph.D., Arne Astrup, M.D., Ph.D., Leann L. Birch, Ph.D., Andrew W. Brown, Ph.D., Michelle M. Bohan Brown, Ph.D., Nefertiti Durant, M.D., M.P.H., Gareth Dutton, Ph.D., E. Michael Foster, Ph.D., Steven B. Heymsfield, M.D., Kerry McIver, M.S., Tapan Mehta, M.S., Nir Menachemi, Ph.D., P.K. Newby, Sc.D., M.P.H., Russell Pate, Ph.D., Barbara J. Rolls, Ph.D., Bisakha Sen, Ph.D., Daniel L. Smith, Jr., Ph.D., Diana M. Thomas, Ph.D., and David B. Allison, Ph.D.

BACKGROUND

Many beliefs about obesity persist in the absence of supporting scientific evidence (presumptions); some persist despite contradicting evidence (myths). The promulgation of unsupported beliefs may yield poorly informed policy decisions, inaccurate clinical and public health recommendations, and an unproductive allocation of research resources and may divert attention away from useful, evidence-based information.

METHODS

Using Internet searches of popular media and scientific literature, we identified, reviewed, and classified obesity-related myths and presumptions. We also examined facts that are well supported by evidence, with an emphasis on those that have practical implications for public health, policy, or clinical recommendations.

RESULTS

We identified seven obesity-related myths concerning the effects of small sustained increases in energy intake or expenditure, establishment of realistic goals for weight loss, rapid weight loss, weight-loss readiness, physical-education classes, breast-feeding, and energy expended during sexual activity. We also identified six presumptions about the purported effects of regularly eating breakfast, early childhood experiences, eating fruits and vegetables, weight cycling, snacking, and the built (i.e., human-made) environment. Finally, we identified nine evidence-supported facts that are relevant for the formulation of sound public health, policy, or clinical recommendations.

CONCLUSIONS

False and scientifically unsupported beliefs about obesity are pervasive in both scientific literature and the popular press. (Funded by the National Institutes of Health.)

Myths, Presumptions, and Facts about Obesity — NEJM

Resistance training among young athletes: safety, efficacy and injury prevention effects

A D Faigenbaum¹ and G D Myer^2,3,4

Abstract

A literature review was employed to evaluate the current epidemiology of injury related to the safety and efficacy of youth resistance training. Several case study reports and retrospective questionnaires regarding resistance exercise and the competitive sports of weightlifting and power-lifting reveal that injuries have occurred in young lifters, although a majority can be classified as accidental. Lack of qualified instruction that underlies poor exercise technique and inappropriate training loads could explain, at least partly, some of the reported injuries. Current research indicates that resistance training can be a safe, effective and worthwhile activity for children and adolescents provided that qualified professionals supervise all training sessions and provide age-appropriate instruction on proper lifting procedures and safe training guidelines. Regular participation in a multifaceted resistance training programme that begins during the preseason and includes instruction on movement biomechanics may reduce the risk of sports-related injuries in young athletes. Strategies for enhancing the safety of youth resistance training are discussed.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3483033/

Longitudinal Examination of Age-Predicted Symptom-Limited Exercise Maximum Heart Rate

Na Zhu,^*,1 Jose Suarez,^*,1 Steve Sidney,² Barbara Sternfeld,² Pamela J. Schreiner,¹ Mercedes R. Carnethon,³ Cora E. Lewis,⁴ Richard S. Crow,¹ Claude Bouchard,⁶ William Haskell,⁵ and David R. Jacobs, Jr^1,7

Abstract

Purpose

To estimate the association of age with maximal heart rate (MHR).

Methods

Data were obtained in the Coronary Artery Risk Development in Young Adults (CARDIA) study. Participants were black and white men and women aged 18-30 in 1985-86 (year 0). A symptom-limited maximal graded exercise test was completed at years 0, 7, and 20 by 4969, 2583, and 2870 participants, respectively. After exclusion 9622 eligible tests remained.

Results

In all 9622 tests, estimated MHR (eMHR, beats/minute) had a quadratic relation to age in the age range 18 to 50 years, eMHR=179+0.29*age-0.011*age². The age-MHR association was approximately linear in the restricted age ranges of consecutive tests. In 2215 people who completed both year 0 and 7 tests (age range 18 to 37), eMHR=189–0.35*age; and in 1574 people who completed both year 7 and 20 tests (age range 25 to 50), eMHR=199–0.63*age. In the lowest baseline BMI quartile, the rate of decline was 0.20 beats/minute/year between years 0-7 and 0.51 beats/minute/year between years 7-20; while in the highest baseline BMI quartile there was a linear rate of decline of approximately 0.7 beats/minute/year over the full age of 18 to 50 years.

Conclusion

Clinicians making exercise prescriptions should be aware that the loss of symptom-limited MHR is much slower at young adulthood and more pronounced in later adulthood. In particular, MHR loss is very slow in those with lowest BMI below age 40.

Keywords: prediction equations, graded exercise test, mixed models, epidemiologic study

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2891874/

Treatment of obesity: need to focus on high risk abdominally obese patients

Jean-Pierre Després, professor,^a Isabelle Lemieux, PhD student,^b and Denis Prud'homme, professor

Summary points

• A simple measurement such as waist circumference can indicate accumulation of abdominal fat
• Viscerally obese men are characterised by an atherogenic plasma lipoprotein profile
• A triad of non-traditional markers for coronary heart disease found in viscerally obese middle aged men (hyperinsulinaemia, raised apolipoprotein B concentration, and small LDL particles) increases the risk of coronary heart disease 20-fold
• Four out of five middle aged men with a waist measurement 90 cm and triglyceride concentrations 2 mmol/l are characterised by this triad
• Even in the absence of hypercholesterolaemia, hyperglycaemia, or hypertension, obese patients could be at high risk of coronary heart disease if they have this “hypertriglyceridaemic waist” phenotype

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1119905/

The Crucial Role of Recess in School

COUNCIL ON SCHOOL HEALTH

AAP—American Academy of Pediatrics


Recess is at the heart of a vigorous debate over the role of schools in
promoting the optimal development of the whole child. A growing trend
toward reallocating time in school to accentuate the more academic
subjects has put this important facet of a child’s school day at risk.
Recess serves as a necessary break from the rigors of concentrated,
academic challenges in the classroom. But equally important is the
fact that safe and well-supervised recess offers cognitive, social,
emotional, and physical benefits that may not be fully appreciated
when a decision is made to diminish it. Recess is unique from, and
a complement to, physical education—not a substitute for it. The
American Academy of Pediatrics believes that recess is a crucial
and necessary component of a child’s development and, as such, it
should not be withheld for punitive or academic reasons. Pediatrics
2013;131:183–188


http://pediatrics.aappublications.org/content/131/1/183.full.pdf+html?sid=5027c478-1779-471b-842c-c5dcc4362413