Introduction (proofread)
Exercise is an activity that alters the physiological responses throughout the body and is an important aspect of many peoples lives across the world. The physiological effects of exercise on the human body have been well identified in past literature \cite{Tomporowski_1986}. Exercise levels decline throughout a person's life cycle with one of the largest rates of decline occurring in young adulthood \cite{students}. Young adults, especially students, are faced with the decision of whether or not they should go to the gym.
Research has shown that there are positive effects of exercise. The physiological response to exercise is dependent on multiple factors: the intensity, duration, and frequency of the exercise along with environmental conditions \cite{Burton_2004}. Exercise is a free way to ward off diseases and improves the function of different mechanisms within the body \cite{exercisea}. Although exercise has been shown to affect cognitive function \cite{Tomporowski_1986}, less is known about the effects of exercise on cognitive functioning in athletes versus non-athletes. In our study, the differences in physiological responses of athletes and non-athletes were examined before, during and after moderate exercise. Additionally, the cognitive performance of athletes and non-athletes were examined before and after moderate exercise.
One key physiological difference between athletes and non-athletes is that highly trained athlete's resting heart rate can be as low at 50 BPM while the resting heart rate of a non-athlete can be 70 BPM \cite{Burton_2004}.
Physiological Effects of Exercise
Common known benefits of exercise include helping maintain a healthy cardiovascular system by preventing high blood pressure \cite{Fagard_2007}. Exercising is different for everyone and varies greatly between age groups. Regardless of the type of exercise or age group, exercising has profound effects on the body. These effects can be exhibited mentally, emotionally and physiologically. As a person ages, their brain becomes more developed and is required to know how to perform difficult cognitive tasks. The population becomes segmented into those who exercise frequently and those who do not. College students and adults are busy with studying and work life, therefore have less time for exercise.
The segmentation of individuals who exercise and of those who don't may cause a gap to form in the cognitive abilities of the individuals. If an individual begins to exercise they may experience cardiovascular and cognitive benefits in addition to improvements in physical health. The study will allow baseline values between groups to be compared as well as the immediate effects of exercise on cognition of populations of students with different activity levels. (General techniques used/population.)
The body breaks down or converts most carbohydrates into the sugar glucose. Glucose is absorbed into the bloodstream, and with the help of a hormone called insulin it travels into the cells of the body where it can be used for energy. When a person exercises the body turns to glucose and adenosine triphosphate (ATP) for energy. This energy helps an individual perform quick movements and changes in position as well as aid in muscle contractions needed during exercise \cite{klein}. During exercise, heart rate is increased to allow more oxygen to be pumped throughout the body. Blood containing nutrients and oxygen are delivered to active muscles. This increase in oxygen allows brain cells to function at higher levels \cite{klein}. After exercising for a month, a person will start to feel less tired when they exercise as changes in the heart muscle occurred to adapt to the increased load of exercising \cite{on}.
Exercise also triggers neurotransmitters to be released from the brain. Among these neurotransmitters are endorphins and gamma-aminobutyric acid (GABA). Endorphins help reduce pain signals and GABA helps to improve mood and decrease anxiety when released \cite{endorphins}. Furthermore, brain-derived neurotrophic factor (BDNF), a protein which has key roles in learning and memory, has been found to be related to exercise (Rasmussen et al. 2009). BDNF works on neurons, to regulate their maintenance, growth, and survival (Rasmussen 2009). Rasmussen et al. (2009) found that during exercise in humans, the release of BDNF from the brain was two to three times the amount at rest. This finding suggests that exercise may be a great way to improve connections in the brain through neuron growth and regulation since BDNF release is higher during exercise than rest \cite{Rasmussen_2009}. Cotman and Berchtold (2002) also studied BDNF and exercise and suggest that exercise can benefit the functioning of the brain overall, benefit cognitive functioning, and help to prevent damage to the brain in the future \cite{Cotman_2002}.
Cognitive Effects of Exercise
Throughout past research, studies have found that people who exercise self-report that physical activity affects their mental abilities, but the direction of the reported effect is not consistent throughout the literature (Tomporowski & Ellis, 1986). While people report that exercise affects their cognitive abilities, there is also experimental evidence. For example, Hillman conducted a study of existing research on the influence exercise has on brain functioning \cite{Hillman_2008}. From their research, Hillman, Erickson, and Kramer found that in human and non-human studies, exercise and aerobic fitness can have positive effects on various aspects of cognitive functioning, however, most of the research is done in populations of older adults. For our study, we would like to study college-aged populations, specifically non-athlete and athlete college-aged populations. \cite{Jacobson_2014} strived to discover how cognitive performance differs in athletes versus non-athletes. To measure cognitive performance, the researchers tested for the executive functioning of everyone in their study by having participants complete the Delis- Kaplan Executive Function System (D-KEPS) Tower Test and the Color-Word interference test \cite{Jacobson_2014}. Jacobson and Matthaeus (2014) found athletes performed better on some of the executive functioning testing compared to the non-athlete group. This study focused on long term exercise in athletes and the effects on cognitive functioning. In our study, however, we looked at the more short-term effects of cognitive functioning directly after exercise.
For our study, we have developed two hypotheses. Our first hypothesis is that athletes will have a lower resting heart rate than non-athletes along with a lower heart rate during and after moderate physical activity. Our second hypothesis is that when compared to their pre-exercise cognitive task score, non-athletes will perform worse on their post-exercise cognitive task when compared to athletes.
Methods
The study population was comprised of female students currently enrolled at Clarkson University in Potsdam, New York. Eighteen students participated in the study and ranged in age from 18 to 22 years old. Two subsets of volunteer subjects participated in this study: students competing on a Division III sports team at Clarkson University and students not competing on a DIII sports team at Clarkson University. Students who are a member of a DIII sports team are classified as "athletes" and the students who are not a member of a sports team are classified as "non-athletes". Due to time constraints, studying a larger population of students was not feasible. Using such a small set of participants may skew the data.
Procedure 1: Electric Blood Pressure Monitor
The study was performed using an electric blood pressure monitor to measure the blood pressure and pulse of the participants. The participant rested their arm on the table and the sleeve of the electric blood pressure monitor is placed on their arm. It is important that the arrow on the sleeve aligned with the artery of the participant. After the sleeve was fastened, the start button was pressed and the participant's blood pressure and pulse was taken and reported on the monitor's screen.
Procedure 2: Heart Rate
The participant will fasten an Apple Watch to their wrist, which will allow heart rate to be recorded throughout the duration of the experiment. Heart rate is taken by pressing the heart button on the screen. During the exercise, a stair-stepping exercise program was run on the Apple watch to record the heart rate throughout and the average heart rate during the two minutes.
Procedure 3: Cognitive Task (Math)
The participant completed as many multiplication and division questions as they can in a minute. The participants will receive different sets before and after. The cognitive test was set up ahead of time to minimize time lost from the participant finishing the step-up exercise to the time they performed the cognitive test.
Procedure 4: Exercise (Step-ups)
The participant performed step-ups on at 10 inch step for two minutes. A step-up exercise is like running in place, but instead of running, the participant steps up and down from an elevated surface in place. The participant performed the step ups to the beat of a metronome (135) so that the pace was kept constant. All of the prior measurements were repeated following the exercise. Repeat steps 1-3 after exercise is completed.
Data Analysis
Using SPSS we analyzed the overall descriptive statistics and the correlations among the Data. For our main analysis we used a between groups design and ran ANOVAs to analyze the differences in each dependent variable.