NUTRITION IN SPORT

(Martin Jones) #1

always commence with ‘simple’ dieting. In a
comprehensive review of eating disorders in
young athletes, Wilmore (1995) concluded that
athletes are at an increased risk of eating
disorders, particularly female athletes in
endurance sports or appearance sports. Dieting
is also likely to contribute to suboptimal peak
bone mass in early adulthood and early osteo-
porosis in the long term (Bailey et al. 1996).
Dieting and vegetarian diets nearly always con-
tribute to iron deficiency. Iron deficiency is a
major problem in adolescence, occurring in boys
as well as girls (Kurz 1996). This is likely to con-
tribute to reduced physical activity and hence
reduced peak bone mass, reduced immunity
and, though not proven, reduced cognitive
function.
Although, in contrast to their non-athletic
peers, adolescent athletes are concerned with
regard to their nutrition, studies have shown that
their dietary intake may be less than adequate
(Perron & Endres 1985; Lindholm et al. 1995).
Martinezet al. (1993) found in a group of male
high school American football players that the
majority consumed inadequate food energy, iron
and calcium, when compared to recommended
dietary allowances (RDA), and consumed too
much salt. However, as no measures of body


mass were recorded, it was not possible to deter-
mine whether this shortfall in RDAs resulted in
progressive weight loss. What is suggested is
that these male athletes did not have any
better or worse dietary habits than other male
teenagers (Martinez et al. 1993). Studies of
adolescent female athletes have also found that
energy intakes are significantly lower than esti-
mated energy needs (Perron & Endres 1985;
Lindholmet al. 1995). A Swedish study compared
the nutritional intake of 22 elite female gymnasts
(age range, 13.5–16.6 years) and 22 healthy girls
(age range, 14.1–15.9 years). This study found
that both groups had energy intakes below their
estimated energy needs, but this did not seem
to influence their health status (Lindholm et al.
1995). One criticism of this type of study relates
to the interpretation of recommended RDAs.
How valid are RDAs for children? Can standard
recommendations for a child of average weight
at a given chronological age be used for com-
parison with an elite young gymnast, especially
given the fact that elite gymnasts are known to be
small for their chronological age, due in part to
their late sexual development (Baxter-Jones &
Helms 1996)? It is therefore suggested that a
gymnast’s recommended RDA would be lower
than the average child’s.

the young athlete 431


Fig. 32.1Adolescents excel in
some sports: gymnastics,
especially women’s gymnastics,
has traditionally been dominated
by young performers. Small
stature and low body fat content
are also characteristic of elite
performers. Photo © Allsport.

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