Early puberty and the years immediately prior to pubertymay be particularly
opportune to harness the osteogenic potential of exercise in the
presence of increasing levels of circulating growth factors [8].
Women aremore likely to suffer fromosteoporosis thanmen [9] and
less likely to exercise, including during childhood [10,11]. In addition,
sexual dimorphism of bone development during growth results in
greater bone strength in boys than girls following puberty [12–14].
In-school exercise interventions are an effective strategy to broadly
increase the physical activity levels of both sexes [15]. Exercise
programmes that incorporate brief but high rate of loading activities
such as jumping (for weight bearing bones) or tennis (upper extremity
bones) induce the greatest gains in bone [6,16], while longer duration
aerobic activities have historically been utilised to minimise the accumulation
of fat and optimise cardiovascular health [17,18]. A recent
meta-analysis of the outcomes of exercise interventions designed to
enhance paediatric bone revealed that osteogenic exercise may also
reduce fat [19]. It was not known if an exercise programme designed
to specifically target both tissues would be effective