Effects of 3 hours a week of physical activity on body fat and cardio-respiratory parameters in obese boys

Abstract

The prevalence of overweight or fat children and adolescents has markedly increased in Hungary during the past three decades. Among the possible factors insufficient physical activity and a relative or absolute excess of calorie intake associated to it can be regarded as the most important ones. The aim of the study was to analyse the effects of a 20-week aerobic exercise on body composition and on the exercise tested cardio-respiratory functions in 10-year-old obese boys. Obesity was defined by a BMI greater than the cut-off value reported by Cole and co-workers (5) and a relative body fat content above 30% (13). Of the study group 21 volunteer children completed the program; the contrast group contained 28 obese boys. Mean calendar age was 10.03 +/- 0.26 in the study group (S) and 9.88 +/- 0.29 in the control group (C). The members of group S had two curricular physical education (PE) classes a week and three extracurricular aerobic physical activity sessions of 60 min net time in the afternoon, on Mondays (swimming and water games), Wednesdays (folk dance) and Fridays (soccer). Group C had only 2 PE classes a week. Anthropometric and spiroergometric data were collected in the middle of January and June of 2004. Relative body fat content and BMI did not increase during the observation period in contrast to the significant increase of both in the control group. Peak minute ventilation, aerobic power, oxygen pulse, and running distance (performed on a treadmill) increased in group S, and did not change in group C. The program was considered successful despite that the changes in the observed physiological and physical indicators appeared to be slight. However, the 5-month elevated level of physical activity brought about such development in the physical status of the obese subjects that might be an appropriate basis for regular training. Fortunately, the cardio-respiratory functions of the investigated boys were not affected yet by obesity, consequently the really dramatic change in their further lifestyle exclusively depends on their decision.

Improvement of aerobic fitness in obese children: a meta-analysis

“…The characteristics of the nine studies (32–40) are listed in Table I. Six were randomized controlled trials (RCT) ( n = 208) and three were controlled clinical trials (CCT) ( n = 103).…”

“…The type, duration, and frequency of the exercise intervention varied among the studies. Only four studies reported the attendance, the median being 72% in the aerobic programs (range 54–90%) (33,36) and 74% in the combined programs (range 66–83%) (37,38). Table II presents the results corresponding to applying the methodological quality criteria for each item of the Delphi list (24).…”

“…The analysis included a total of 311 children. Three studies were of boys only (32,36,39) and one of girls only (35). The other studies had a predominance of boys (83.3%) (40) or girls (64–68%) (33,37), or the two genders were roughly equally distributed (34,38).…”

“…This is a problem of methodological inconsistency which constitutes an obstacle to the global study of childhood obesity (41). Three studies (36,38,39) used the classification criteria of the International Obesity Taskforce from the 97th BMI percentile (42). Two studies used the criteria of the National Health and Nutrition Survey (43) from the 85th triceps skinfold percentile (33) and the 95th BMI percentile (35).…”

Is Physical Fitness Associated With Health in Overweight and Obese Youth? A Systematic Review

“…An additional eight studies (Adam, Westenhofer, Rudolphi, & Kraaibeek, 2009; Eliakim et al, 2002;Gately, Barth, Radley, & Cooke, 2005; Gately et al, 2005; Ildiko et al, 2007; Naylor et al, 2008; Stella et al, 2005; Vajda et al, 2007) were also considered for the review but were excluded, because they were deemed “quasi-experimental” since it was not clear that intervention and control group assignments were randomized. Two other studies (Watts et al, 2004; Watts et al, 2004b) used a randomized cross-over study design (with participants serving as their own control in “trained” and “untrained” phases), but it was unclear if there was a potential carry-over effect due to an insufficient wash-out period to minimize residual effects on fitness or health for the group that “trained” first then became “untrained” later.…”