Body mass index, fitness and physical activity from childhood through adolescence

Abstract

BackgroundObesity, sedentary lifestyle and poor cardiorespiratory fitness in childhood may increase the risk of health problems later in life.PurposeThe authors studied the association of early childhood weight status with cardiorespiratory fitness and leisure-time physical activity (LTPA) in adolescence. The stability and associations of LTPA and fitness from childhood through adolescence were also studied.MethodsBody mass index (BMI) was assessed annually since birth in a prospective, longitudinal study. The mean BMI between ages 2 and 7 years indicated weight status at preschool age. Fitness was studied with a shuttle run test at age 9 and with a maximal cycle ergometer test at age 17. The same questionnaire was used to assess LTPA at age 9, 13 and 17. Complete data on preschool BMI, LTPA at ages 13 and 17 and fitness at age 17 years was provided by 351 children, while fitness and LTPA data were available for 74 children at ages 9 and 17.ResultsPreschool BMI was inversely associated with fitness in adolescence independently of adolescent LTPA (p=0.0001). Children who had a high preschool BMI but whose weight status was reduced in adolescence had similar fitness in adolescence as the children with a persistently low BMI. Regardless of the fitness level in childhood, the children whose LTPA increased between age 9 and 17 had a similar adolescent fitness level as persistently active subjects.ConclusionsIt is important to maintain a healthy body weight and a physically active lifestyle from very childhood through adolescence to improve fitness during adolescence.

Growth Development and Maturity in Children and Adolescent: Relation to Sports and Physical Activity

“…This rise in strength has an impact on the capacity for motor skill performance in fitness activities and in the prevention of injuries during such activities. Since the increase in testosterone production in adolescent children is markedly higher in boys than girls, boys become stronger faster and to a higher degree [6,7,8]. Whole-body activities are more important and beneficial than the same exercises used for post-pubescent athletes.…”

“…Middle-childhood-aged children also refine their control over gross motor skills, learning to master where they hop, skip, throw, and jump. They are able to gain this improved control and coordination due to increases in their flexibility, balance, and agility [6,7,8]. Children at this age also learn how to synchronize the movement of their body's various parts, allowing for the development of smoother, more coordinated whole-body movement routines such as are needed for participating in organized sports.…”

“…Before puberty, improvement concerns mainly nerve activation. Other mechanisms, including improved elastic energy release, intensified excitation-contraction coupling, and improvement in strength transmission to different bone levers, are also involved [6,7,8]. This rise in strength has an impact on the capacity for motor skill performance in fitness activities and in the prevention of injuries during such activities.…”

“…Before puberty, maximum strength in boys and girls remains relatively similar. Improved nerve activation and increased muscle mass (hypertrophy) are the main explanation for the increase in strength [6,7,8]. Before puberty, improvement concerns mainly nerve activation.…”

“…Strength and power rapidity increase in proportion to muscle mass under the influence of hormonal activity. The daily use of motor activities, games and physical education must allow children to acquire a set of motor skills i.e., gross motor skill development [6,7,8]. During middle childhood, children continue to build on and improve gross motor skills; the large-scale body movement skills such as walking and running that they first learned during earlier developmental stages.…”