Question

Body builders consume large volumes of dietary supplements, especially products that combine creatine with whey proteins, a waste product of cheese making. In a study to assess the impact of creatine and whey on strength and muscle fiber characteristics, 28 highly trained body builders in their mid-20s were recruited for a 13-week dietary study.

The researchers divided the volunteers into four groups, giving each man the same caloric bonus per day: a flavored drink containing a gram of supplement per kilogram of body weight. One supplement contained just carbohydrates, another just whey powder, and the last two a mix of creatine with either carbohydrates or whey. The experiment was conducted as a double blind with neither the athletes nor the scientists knowing who received each supplement until the study was completed.

Throughout, the men performed supervised resistance training three times a week and all experienced strength gains. Below are the data for increases in beach press totals in kilograms for the 28 body builders.

Carbohydrate only	Whey only	Creatine & carbohydrate	Creatine & whey
3	5	7	11
5	3	8	9
2	5	10	15
5	4	7	9
1	7	5	12
4	4	4	10
8	5	9	5

(i): Test the hypothesis.

(ii): Analyze with one-way ANOVA to test the hypothesis that there is any significant differences in the heights among the three fertilizer treatments at both:

(a): 95% and 90% level of significance.

Answer 1

at 0.1 significance level