1. Subjects are to be randomly allocated to low-intensity exercise (LIE; 50% APMHR) or high-intensity exercise (HIE; 95% APMHR). Subjects will be exercised on a cycle ergometer for 3 minutes at either 50% APMHR (LIE) or 95% APMHR (HIE). After a 3-day recovery period, subjects will perform the other exercise type. Prior to beginning the exercise, a finger-stick blood sample will be obtained to determine blood lactate concentration at rest and then immediately upon termination of the exercise bout. All significant differences will be determined using a level of significance of 0.05.

Figure 1. Blood lactate concentration before and after LIE or HIE. Data are reported as means +/- standard deviation. n = 20 per group.

The statistical analysis revealed the following findings:

1. LIE vs. HIE Resting: p= 0.878
2. LIE Peak Exercise vs. LIE Resting: p=0.043
3. HIE Peak Exercise vs. HIE Resting: p=0.005
4. HIE Peak Exercise vs. HIE Peak Exercise: p=0.015

1. Which of the comparisons above are statistically meaningful, based on the a-priori alpha level? Why? (1 point)

Comparison number 1

2. What is the probability that the statistically significant differences found are due to chance? (1 point)

3. The statistical analysis of the data revealed that the power of the test performed was 0.821.

1. Provide a written interpretation of this power value. What does this 0.821 value mean? Is this value acceptable? High? Low? (1 point)

2. What was the associated beta rate for the test? Be sure to provide a brief interpretation of this value. (1 point)

4. How many total subjects were in the study? (1 point)

Blood Lactate (mmol/L) 14 12 10 8 2 0 LIE HIE Resting Condition Peak Exercise