The Effects of Exercise on Thinking
	Elio has a theory that regular exercise can improve thinking.  The first step in testing a theory is to develop a hypothesis.  My hypothesis for this experiment is that regular exercise improves thinking.  There are two variables in this experiment, the independent and the dependant variable.  The independent variable is defined as the experimental factor that is manipulated and whose effect is being studied.  The independent variable in this experiment is the amount of exercise over a period of one month.  The dependant variable is defined as the variable that may change in response to manipulations of the independent variable.  The dependant variable in this experiment is the IQ test results given at the beginning and end of the one month period.
	The next step is to determine who the participants in the experiment will be.  I will choose these people through the method of random selection. Random selection is defined as choosing a sample that fairly represents a population because each member has an equal chance of inclusion.  In this experiment, the population will be composed of 100 randomly selected men and women between the age of 18-60 with no known physical disabilities that would prevent them from regularly exercising, and who do not currently exercise regularly.  I will use random assignment, which is defined as assigning participants to experimental and control conditions by chance, minimizing preexisting differences between those assigned to the different groups.  I will make the sample group of 100 adults randomly pick a card out of
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a container.  The card will either have the number one or two written on it.  This will determine how the group will be divided into the experimental and control groups.  Individuals who chose the number one will make up the control group, while individuals who chose the number two will make up the experimental group.  The experimental group is defined as the group that exposes participants to the independent variable.  In my experiment, this group will exercise for one hour every day for one month.  The control group is defined as the group that contrasts with the experimental group, and serves as a comparison for evaluating the effect of the experiment.  In my experiment, the control group will not exercise at all for one month.
	I predict that the experimental group, who will exercise one hour per day for a month, will show significant improvement between the IQ test given at the beginning of the month before they began exercising, and the IQ test given at the end of the month.  I believe that the regular exercise will improve blood flow to the brain, in turn giving it more oxygen, ultimately improving thinking.  I also predict that the control group, who will not exercise during the month, will show no significant change in test scores between the IQ test given at the beginning and end of the month.