Cardiovascular Training Among Children
The current research clearly identifies the importance of physical activity and physical fitness to one’s health both in adults and children. However, taking into account the current low levels of physical activity and fitness among children, it is crucial that physical activity and fitness be promoted beyond the school and school day and into the home and community.
One of the key components of Physical Fitness is the development of the cardiovascular system. Thus, the purpose of this article is to discuss the cardiovascular adaptations to aerobic exercise in children as well as its practical application.
Cardiovascular Adaptations to Aerobic Exercise:
The cardiovascular system of children seems to respond differently to exercise when compared to adults (Braden et.al., 1990 & Turley, 1997). One of the main adaptations to aerobic training is the ability of the heart to increase its pumping capacity (Cardiac Output L/min-CO)in response to increasing work load which in turn bring about an increase in one’s maximum oxygen consumption(Vo2Max). The initial increase in CO at the onset of exercise is met by an increase in Heart Rate (HR) and Stroke Volume (SV).Stroke volume usually increases up to an intensity of 50 to 60% of one’s Vo2Max, whereas, HR continues to increase to maximal intensity. Similar to adults, children who undergo a well controlled aerobic training program (i.e., treadmill running at > 80% of Vo2Max, 3x wk/ 1hr – 13 weeks)do improve their cardiovascular fitness (i.e., Vo2Max).
The Vo2Max increases in children, however, are lower (5 to 10%) than those usually seen in adults for similar training programs -15 to 30% (Turley, 1997; Mandigout et.al., 2001). For instance, children have lower cardiac output at a given oxygen consumption (VO2) when compared to adults. In addition, heart rate recovery has been reported to be faster in children as compared to adults (Turley, 1997). Further, there appears to be no differences in gender as related to gains in cardiovascular fitness in children after an aerobic training program (Mandigout et.al., 2001 & Obert et.al., 2003).
In summary, children can increase their cardiovascular fitness when engaged in an aerobic training program.
In order to improve the cardiovascular component of physical fitness the following guidelines should be taken into consideration when developing a supervised conditioning program for children. *Note that each child should receive an individualized program based on his/her strengths and weaknesses. The program described below is just a sample.
• Frequency: 3 times per week.
• Intensity: Moderate.
• Duration: 30 to 40 minutes.
• Phase: 4 weeks.
• Warm Up: 8 to 10 minutes. It should include dynamic activities such as brisk walking, skipping, light jogging, and jumping jacks followed by static stretching (i.e., calf, hamstrings, lats).
• Aerobic Activity: Begin with 5 to 10 minutes total and gradually increase the duration at 5 minute increments up to 25 to 30 minutes (i.e., walking, cycling, swimming, jogging).
Cool Down: Static stretches: Hamstring; quadriceps; calf; lats; piriformis, and neck.
In addition, according to the Council for Physical Education for Children (COPEC, 1998), children should be involved in physical activity on most days of the week for 30 to 60 minutes (i.e., moderately intense activity).
In conclusion, children can improve their cardiovascular system when properly trained.
Thus, given the evidence that both increased physical activity and physical fitness in children are associated with improved risk factors for cardiovascular disease (Sallies, Patterson, Buono & Nader, 1988; Despres, Bouchard & Malina, 1990; DuRant, Baranowski, Rhodes, Gutin, Thompson, Carroll, Puhl & Greaves, 1993; Caspersen, Nixon & DuRant, 1998), it is important that children participate in a variety of physical activities to develop and maintain an acceptable level of cardiovascular fitness.
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Caspersen, C., Nixon, P., & DuRant, R. (1998). Physical activity epidemiology applied to children and adolescents. Epidemiology, pp. 341-403.
Council for Physical Education for Children-COPEC. (1998). Physical activity for children: A statement of guidelines. Reston, VA: NASPE.
Despres, J., Bouchard, C., & Malina, R. (1990). Physical activity and coronary heart disease risk factors during childhood and adolescence. Exercise and Sport Science Review, 18, 243-261.
DuRant, R., Baranowski, T., Rhodes, T., Gutin, B., Thompson, W., Carroll, R., Puhl, J., & Greaves, K. (1993). Association among serum lipid and lipoprotein concentrations and physical activity, physical fitness, and body composition in young children. The Journal of Pediatrics, 123(2), 185-193.
Mandigouts, S., Lecoq, AM., Courteix, D., Guenon, P. & Obert, P. (2001). Effect of gender in response to an aerobic training programme in prepubertal children. Acta Pediatric, 90, 9-15.
Obert, P., Mandigouts, S., Nottin, S., Vinet, A., N’Guyen, L.D. & Lecoq, AM. (2003). Cardiovascular responses to endurance training in children: effect of gender. European Journal of Clinical Investigation, 33, 199-208.
Sallis, J., Patterson, T., Buono, M., & Nader, P. (1988). Relation of cardiovascular fitness and physical activity to cardiovascular disease risk factors in children and adults. American Journal of Epidemiology, 127(5), 933-941.
Turley, K.(1997). Cardiovascular responses to exercise in children. Sports Medicine, 24(4), 241- 257.