Energy intake profile in the triathlon competition by means of cluster analysis.

The subjects were 18 male triathletes competing in the 4th Kaike Triathlon held at Tottori in 1984. Answers to a questionnaire on dietary and water intake before and during the competition were analysed. Cluster analysis using the average distance method was applied to 21 variables relating to order, age, stature, body weight, total calorie intake and each nutrient element ingested during three periods: after swimming, during cycling and during the marathon. The arrival order was clustered with stature and weight, and its similarity showed 69.7 when the first cluster formed. Age along with carbohydrate, protein or water intake during the marathon formed secondary clusters with order, stature, and weight (similarity: 60.0). In the upper place group, breakfast calories occupied the largest portion of 26.1% and the smallest portion of 17.2% during the marathon running. Furthermore the group ingested more energy than the other groups during cycling.