Benefits of Exercise for Children Tested

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Summary
The Early Sport PE Effectiveness Testing Protocol was designed to demonstrate the health benefits for children (3rd and 6th Grade elementary students) of regular physical activity in school, by maintaining a significantly elevated heart rate (between 135-190 bpm) for most (50%+) of the PE lesson period.

Silver Mesa Elementary was selected in a mixed middle class neighborhood in a bedroom community adjacent to Salt Lake City, Utah. With the full cooperation of Jordan School District, (with 74,000 students, one of the 50 largest districts in the country; Dr. Barry Newbold, Superintendent; Julie Christofferson, District PE Coordinator), Silver Mesa (Denise Orme, Principal) volunteered to have its students participate in the test. The school had a total enrollment of 477; with 80 students in three 3rd Grade classes, and 82 in three 6th Grade classes. Study and Control groups were randomly selected from these, with equal numbers of students in each.

After the appropriate parental consent was provided (see Parental Consent Form attached), every participant had blood drawn by certified phlebotomists (services donated by IASIS Healthcare Corporation) at baseline and following the five weeks of the Early Sport daily physical activity program. Individual blood profile data was obtained (with lab analysis by IASIS) for both the Study group and the Control group.

Integral to the Testing Protocol, analysis was provided for the following blood components:

Total Cholesterol: A known risk factor for coronary heart disease when greater than 180mg/dL1.
Triglycerides: Abnormalities are linked to decreased clearance of VLDL2. A level over 250 mg/dL is considered to be a major risk factor for Type 2 diabetes3. Hypertriglyceridemia, defined as at least 200 mg/dL, is associated with an increased risk of cardiovascular heart disease mortality4.
HDL-C: Low levels of this protective cholesterol raise risks of cardiovascular disease by impairing endothelial (blood vessel) wall function5. Higher HDL levels remove excess cholesterol to the liver6 and are considered to be cardioprotective7. HDL may have direct antioxidant and anti-inflammatory effects on the vessel wall7. HDL cholesterol below 35 mg/dL is considered to be a major risk factor for Type 2 diabetes3.
LDL-C: High levels increase the deposition of cholesterol in the arterial wall and the risk of heart disease and a reduction in protective HDL1. LDL is the main cholesterol-carrying lipoprotein.
VLDL-C: Obese children usually have elevated concentrations of serum triacylglycerol - a surrogate measure of VLDL cholesterol - and low concentrations of HDL cholesterol. Occlusive disease is associated with concentrations of large VLDL2.
Chol/HDL Ratio: Non-HDL cholesterol has been suggested as more predictive of cardiovascular risk than LDL cholesterol alone9. The lower the Cholesterol to HDL ratio, the lower the heart disease risk.
HbA1c: An indicator of elevated blood sugar, which is an indicator of diabetes risk (when greater than 6.5%), and cardiovascular disease risk8.
CRP: Raised levels are associated with higher HbA1c levels9, cardiovascular disease risk10, and ischemic heart disease risk11. Elevated CRP is a "powerful independent" risk factor for diabetes12. "CRP has emerged as one of the most powerful predictors of cardiovascular risk."13 Overweight children have higher concentrations of C-reactive protein and higher white blood cell counts, indicating low-grade systemic inflammation, which may predict future cardiovascular disease and diabetes14.

In addition to blood profiles, the Testing Protocol had each student tested, both pre- and post test period, on the proprietary "TriFit" machine (donated by Polar Electro, Inc.) which measured and recorded weight, arm strength (biceps), and flexibility (sit and reach). (The blood pressure device was unavailable at pre- and post test.) Height was also measured.

Cardiovascular endurance performance was measured by the Testing Protocol at baseline and again post-program by having all students (Study subjects and Controls) run for 10 minutes around a course measuring 150 yards, and marked every 10 yards. Instructions on regulating pace (135-190 bpm, each participant wore a heart rate monitor [HRM]) to be able to run continuously for the allotted time were given, with walking or stopping when necessary also cited as options.

Heart rate monitors (donated by Polar Electro, Inc.) were also placed on each Study participant in every PE lesson. These recorded individual heart rate data, which was downloaded to individual files in a central data base. Students were encouraged to regulate their physical activity during classes so as to remain within their target heart rate range for as much of the PE lesson as possible (lower limit 135 bpm, upper limit 190 bpm - monitors on the students' wrists were set to beep and flash whenever a wearer's heart rate was outside the target zone.)

The Early Sport PE program used at Silver Mesa consisted of 3rd and 6th graders having a daily (4-5 times per week, 30-40 minutes each lesson) series of lessons and games, each with warm-up, flexibility, and strength components, described and illustrated in detail on individual lesson cards. The games fall broadly into three groups; the non-competitive play of Large Ball Games, Small Ball Games, and EarlyGoals Circuit Activities. In addition to allowing individuals to participate and progress at their own pace, an objective was to provide students with the opportunity to acquire the skills necessary for an active lifestyle and participation in many sports. (Early Sport teaches individual sport skills, but not the playing of the sports themselves.)

Overriding the skills acquisition aspect is the Early Sport goal of encouraging individuals to maintain an elevated heart rate throughout the lesson, (as indicated by staying in the heart zone noted above), that would improve cardiovascular endurance.

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