The aim of this doctoral dissertation was to determine the effects of a 12 week highintensity
interval training and recreational football on health-related fitness parameters in
overweight male children. The study involved 42 boys classified as overweight or obese, aged
11-13 years, who were randomly devided in three groups each with 14 participants: high
intensity interval training, recreational football and control group. In the group of recreational
football, four boys dropped out from the srudy (n= 10, 11-13 years ± 6 months, 157.9 ± 5.8 cm,
63.7 ± 12.6 kg, BMI 25.4 ± 4.0 kg/m2), due to injuries and lack of time three boys dropped out
high-intensity interval training group (n= 11, 11-13 years ± 6 months, 163.8 ± 9.4 cm, 71.5 ±
10.5 kg, BMI 26.6 ± 3.3 kg/m2), while the number of participants in the control group remained
unchanged until the end of the study (n= 14, 11-13 years ± 6 months, 162.7 ± 9.3 cm, 67.4 ± 16.1
kg, BMI 25.3 ± 4.7 kg/m2). The duration of the training p...rogram was 12 weeks with three
training sessions per week. The training program for the recreational football group lasted 60
minutes, while training for high-intensity interval training group in the first month lasted 36
minutes, in the second month 41 minutes and in the third month the duration was 46 minutes. All
participants were tested in the following health-related fitness parameters, both on initial and
final measurements: body composition, muscle fitness, cardiorespiratory fitness, flexibility and
biochemical parameters. After a 12 weeks training program, the absolute values of maximal
oxygen uptake (VO2max) significantly increased (p<0.05) in high-intensity interval training
groupp<(81.22%, ES = 1.03) and recreational football group (79.83%, ES = 1.09), while the
relative value of VO2max increased significantly (p<0.05) only in the group of recreational
football (7.90%, ES = 1.09). Statistically, significant improvements in flexibility was noted
(p<0.05) only in the group of recreational football in variables: lying on the back (30.86%, ES =
1.35) and flexibility in the folding of the body (21.84%, ES = 1.28). In both experimental groups
indicated a statistically significant (p<0.05) decrease in resting heart rate (high-intensity interval
training group (-2.49%, ES = -1.25),recreational football group (-3.59%, ES = -1.21)). The
experimental program of both experimental groups observed a statistically significant
improvements (p<0.05) in agility T-test (high-intensity interval training group (6.01%, ES = -
0.91), recreational football group (17.02%, ES = -1.05)). Also, both experimental groups noted a
statistically significant (p<0.05) increase in the number of erythrocytes in the blood (highintensity
interval training group (8.90%, ES = 1.58), recreational football group (9.11%, ES =
1.80)). The only statistically significant change (p<0.05) achieved in the control group
performing regular sports and physical education classes was the increase in the number of
erythrocytes in the blood (8.17%, ES = 1.21). Based on the results obtained in this dissertation,
we can conclude that both experimental programs – high-intensity interval training and
recreational football were adequat to improve body composition, cardiorespiratory fitness,
muscular fitness, flexibility, and biochemical parameters in overweight and obese boys.. In
contrast, aforementioned parameters remain unchanged during 12 weeks in control group.
Faculty:
Универзитет у Нишу, Факултет спорта и физичког васпитања
