Dietary intake of energy, protein, fat and carbohydrates in female dance students compared to female music students was estimated by a dietary history method. Energy requirement was estimated from body weight and physical activity both by a standard formula and from the measured work intensity during dance training. Meal patterns showed significant differences in four types of meals on week-days and in one type on weekends. The intake of protein, fat and carbohydrates in absolute amounts and the percentage of energy derived from protein were not significantly different between the two groups. The fraction of energy derived from carbohydrates was higher and that from fat was lower in the dancers than in the musicians. Energy intake was of similar magnitude for the dancers and the musicians (8.3 +/- 1.9 MJ vs. 8.3 +/- 1.7 MJ), while the estimated energy requirement was greater for the dancers (10.3 +/- 0.7 MJ vs. 8.9 +/- 0.4 MJ). The reason for the apparent discrepancy between energy intake and energy requirement of approximately 2 MJ in the dancers is not obvious. The energy intake may have been underestimated. Alternatively, the energy requirement may have been overestimated. The resting metabolic rate may have been depressed by years of low energy intake. In addition, as suggested by some authors, training as such may lower the resting metabolic rate as well as the diet-induced thermogenesis.

Background In adult males, cross‐sectional area (CSA) for type II muscle fibers is generally larger than for type I fibers. In this cross‐sectional study the aim was to compare sex‐related CSAs of various muscle fiber types during childhood‐to‐adulthood transition. Methods Percutaneous biopsy samples were obtained from vastus lateralis in 10‐y‐old children (10 males and 5 females) and in young adults (9 males and 7 females). Fiber types were classified by myofibrillar ATPase and CSAs from NADH‐dehydrogenase staining. Results Type IIA were larger than type I fibers in adult males, but not in adult females or children (age x sex x fiber type, P < .002). When including all participants, body weight and sex explained 78% of the variation in type IIA CSA but only body weight contributed for type I. Conclusions Sex‐specific patterns in CSA of the muscle fiber types appears to develop during the transition from childhood to adulthood.

No abstract

A previous study showed that adult female dancers have a high percentage of type I fibres in vastus lateralis, similar to that of endurance-trained female runners or female cross-country skiers. It is not known if dancers already at an early age are characterized by a high percentage of type I fibres or develop a high percentage of type I fibres as a consequence of dance training. Furthermore, the muscle fibre composition of male dancers has not previously been studied. Therefore the aim of the study was to analyse skeletal muscle fibre characteristics in 10-year-old and 20-year-old dancers of both sexes. Age-matched boys and girls whose physical activity was average for their age groups served as controls. Muscle biopsies for histochemical analysis were obtained from vastus lateralis using the percutaneous needle technique. The major finding of the present study was that the vastus lateralis of young dancers of both sexes had a higher percentage of type I fibres than that of controls. Moreover, the higher type I percentage was seen not only in 20 year olds, but also in 10 year olds, who had begun their dance training at a professional level only a few weeks earlier. No significant difference in this respect was found between female and male dancers. In conclusion, the muscle fibre type composition in young dancers of both sexes differs from that of the average individual of the same age and is characterized by a high percentage of type I fibres.

The prescription of psychotropic drugs at a multidoctor district health centre in northern Sweden in 1973, was analysed by means of problem-oriented medical records. Of the 22,000 inhabitants of the district 10,700 consulted the health centre. Psychotropic drugs were prescribed for 11.3% of the patients, corresponding to 5% of the inhabitants of the area. Sixty per cent of the patients received one psychotropic prescription and 90% not more than three. Two-thirds of prescriptions were for women. Hypnotics, sedatives and minor tranquillisers constituted 64% of all prescriptions, major tranquillisers 24% and antidepressants 12%. One fifth of the patients obtained drugs belonging to more than one of the major psychotropic groups during the year. Insomnia, psychoneurosis and depression made up two-thrids of the indications for psychotropic drug therapy. More than thirty different psychotropic drugs were prescribed for the two major indications. There was considerable variation in how the different doctors prescribed drugs for the same indication. Fifty-nine different drug products were prescribed, of which the commonest five constituted more than half of the total number. Individual doctors used from 22 to 38 different psychotropic drugs.