Nutritional supplementation during the preschool years and physical work capacity in adolescent and young adult Guatemalans.

A follow-up study (1988-89) was carried out in 364 rural Guatemalans, 11-27 y of age, who earlier had participated in a nutritional supplementation experiment. Among its objectives was the assessment of the long-term effects of the nutrition intervention on physical work capacity. Subjects and their mothers from two villages had available a high-energy, high-protein supplement (Atole: 163 kcal/682 kJ and 6.4 g protein per serving or 180 mL), whereas in two other villages a low-energy, no-protein supplement (Fresco: 59 kcal/247 kJ per 180 mL) was provided. Consumption was ad libitum. Maximum oxygen consumption (VO2max) at follow-up was significantly greater in Atole compared with Fresco subjects of both sexes. In subjects 14-19 y, exposed to supplementation throughout gestation and the first 3 y of life, Atole males had a significantly higher VO2max (2.62 L/min) than Fresco males (2.24 L/min), the differences remaining significant even after controlling for body weight and fat-free mass; also, there was a significant positive relationship between amount of supplement consumed and VO2max. The supplementation effect in females of similar age was not statistically significant. It is concluded that early nutritional improvements can have long-lasting effects on physical performance.

Predicting body composition from anthropometry and bioimpedance in marginally undernourished adolescents and young adults.

Body-composition prediction equations were developed using data from a sample of 201 female and male Guatemalan ladinos (ie, people of Amerindian-European descent) aged 11-25 y. Fat-free mass (FFM) values were estimated from body density by using the two-component model and age- and sex-specific values for the density of FFM. The root-mean-square error (RMSE) of the best model predicting FFM from a set of simple anthropometric variables was 1.59 kg for females and 1.90 kg for males. The addition of more extensive anthropometry to the set of candidate predictors reduced the RMSE to 1.42 kg for females and 1.88 kg for males. The subsequent addition of a bioelectrical impedance measure (Ht2/R) further reduced the RMSE to 1.32 kg for females and 1.82 kg for males. These results suggest that for a marginally undernourished population with relatively little body fat, simple anthropometrics are as useful as more sophisticated measures for the prediction of body composition.