P ART I Nutritional Concerns of Athletes
CHAPTER 2 CHAPTER 2 Nutritional Concerns of Pregnant and
C. Nutrient Requirements
VIII. SUMMARY
For healthy women experiencing normal pregnancies, regular exercise is not contraindicated, except under specific circumstances. Women who plan to exercise during pregnancy should discuss their plans with their physician and be aware of both the potential risks and benefits that may be experienced. While athletes may suffer poor performances if dietary intakes are inadequate, the consequences of consuming a poor diet while exercising during pregnancy could be far greater.
Clearly, nutrient needs are increased during pregnancy, but most of these needs can be met through the consumption of a well-balanced diet. The exception, recognized by most experts, is iron. A multivitamin and mineral supplement may be necessary during pregnancy, but excessive intake of specific nutrients might be harmful and are not indicated, even for athletes. All supplement use should be discussed with the physician — preferably before conception, since the safety of many supplements during pregnancy is unknown.
Resuming physical activity as soon as 6 weeks postpartum has been shown to be beneficial to women. Although there may be some concern that exercise might alter breast milk production and
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quality, available research suggests that exercising at moderate intensities will not affect milk production or quality. A limited body of research has shown that weight loss can be achieved in overweight and well-nourished women without compromising lactation, but long-term studies are needed before any conclusions can be made. Athletes who are lean and continuing lactation may compromise milk production if caloric intake is restricted.
As with pregnancy, specific nutrient needs are increased, but not to levels that would require supplementation unless usual dietary intake patterns are shown to be inadequate. Women will likely experience a decrease in bone mineral density during pregnancy, but bone mass will likely rebound when lactation ceases.
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