A number of studies concerning muscular efficiency in humans have used competitive cyclists as subjects. It had previously been observed that variation in efficiency could not be explained by differences in cycling technique. The paper “Cycling Efficiency Is Related to the Percentage of Type I Muscle Fibers” (Medicine and Science in Sports and Exercise [1992]: 782–788) reported the accompanying data on x ! percentage of type I (slow twitch) muscle fibers and y ! cycling gross efficiency (the ratio of work accomplished per minute to caloric expenditure):

a. Construct a scatterplot of the data in which the axes intersect at the point (0, 16). How would you describe the pattern in the plot?

b. Does it appear that the value of cycling gross efficiency is determined solely by the percentage of type I muscle fibers? Explain.

Transcribed Image Text:

Observation 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 X 32 37 38 40 45 50 50 54 54 55 61 63 63 64 64 70 70 75 76 у 18.3 18.9 19.0 20.9 21.4 20.5 20.1 20.1 20.8 20.5 19.9 20.5 20.6 22.1 21.9 21.2 20.5 22.7 22.8