My favorite topic during this term was learning about the fast twitch vs slow twitch muscle fibers. Especially with me being an athlete that runs a lot and lifts, it was interesting to know when I use each muscle. I knew that different muscles were used when doing different activities but I didn’t know that fast twitch was for power and slow twitch was for endurance. I also enjoyed learning how you could “switch” the fibers of your body, the more you run, the more your body adapts and enhances the slow twitch muscles. Overall I really enjoyed all of these topics within the course, especially because I want to be a physical therapist. this course is going to help me in the future and really had my interest.

I decided to write about a NY Times article titled “The Heart of a Swimmer vs. The Heart of a Runner” by Gretchen Reynolds.

It’s already a known fact that exercise changes the workings of your heart, it particularly strengthens and enlarges the left ventricle with the increase need for oxygen. However, is there a difference between constantly swimming and constantly running?? A new study in Canada researched the hearts of elite swimmers and runners, they used elitist because they would have been doing these activities for years at high levels and will show an exaggerated difference in the structure/function of the heart. This makes it easier for researchers to see and prove the differences. They took 16 swimmers and 16 runners of different distances specialties, they asked them to visit the lab after not exercising for 12 hours and then to lie quietly. Both had superb heart health, and all had large efficient left ventricles. However they did find a subtle difference, runner’s hearts were able to fill with blood earlier than average and untwist more quickly than those who swam. This could be attributed to the fact that swimmer don’t have to fight gravity during exercise to get blood back to the heart, so it’s uncertain that it gives runners an advantage in that aspect. However, it’s very interesting to see how the slight difference in exercise can change the makeup and function of our bodies so easily! I wonder if their lung capacity and lactate threshold differ as well because they may not be affected by gravity, like the heart is.

https://www.nytimes.com/2019/04/03/well/move/heart-health-swimming-running-exercise.html?searchResultPosition=1

My presentation topic is about ACL tears in men vs women. This injury is so common and devastating to an athlete’s career, it can take them out for a whole year and they may never fully recover. My team alone we had 2 ACL tears last year, and have a total of 5 girls who have had the surgery. I want to find out why this occurs so frequently, and if it occurs in males more than females and if there’s a reason why. I can name more girls than guys who have torn them, but I don’t know whether that’s because of the sport they play or because of their gender. People should be interested because it’s an injury anyone can get, not just athletes and can be devastating to recover from. If there’s ways to prevent this from happening, people should want to know about it. Sorry im a slacker and haven’t done research yet on my topic so I haven’t discovered anything yet.

This week I am writing about why lactate accumulation is advantageous to the body.  Using the article given by Coach Kirkton, I found some reasoning why it helps out the body. The body can experience multiple kinds of muscle fatigues, the first is caused by a build up of K+, which depolarizes the fiber and prevents Na+ channels from recovering. Another type is called “metabolic fatigue” due to the indirect/direct accumulation of metabolites and a decrease in substrates within the fibers. It can also occur from glycogen depletion.  The accumulation of lactate causes a change in pH within the muscle fibers, which actually slows the onset of fatigue. The pH changes from 7.1 to less than 6.7 which causes the solution to be acidic. This acidity increases the Ca concentration and help activate the contraction. The pH also counteracts the inhibitory affects of the raised [K+]. In short, the lactate accumulation helps prevent or slow down the failure of the action potential of the muscle fibers.

I also found another article, titled “Lactate: valuable for physical performance and maintenance of brain function during exercise”.  Not only can lactate slow the high [K+] but also noxious metabolites such as Inorganic phosphates. They also facilitate the removal of muscular proton and acts together with catecholamines to work in reducing fatigue. Lactate also regenerates NAD+ which is used within glycolysis to produce energy. Lactate is also important for cognitive function, it ensures that inhibitory signals within the CNS are detected, so it protects neurons from damage by acidosis.

For a long time lactate has been seen as a waste product but it actually an alternative energy source that the body can use to recover and continue to work. It not only does it help the body during exercise but also when the body is at rest. This is why lactate accumulation is helpful and advantageous for the human body.

Source: https://academic.oup.com/biohorizons/article/doi/10.1093/biohorizons/hzu001/242608#26872984

1. Explain your favorite or most cherished athletic/exercise accomplishment.
   1. My favorite athletic accomplishment was getting my town’s Player of Year position for women’s soccer my senior year of high school. Every year my town takes all high schools in the area and has coaches discussion who the best player is the county. I won, I got a mini photo and had my photo displayed across the county on the newspaper. It was a major honor, that year we won our sectional title for the 5th year in a row, also my fifth time winning because we won our first sectional title my 8th grade year when I first joined the team. It was a nice way to finish off my senior soccer career at my high school, and was a nice way to get a coach’s attention for college soccer. I was able to tell coaches that I had won that prize and that had helped me gain a spot here on Union College Women’s Soccer Team.
2. Why do you think exercise physiology can serve as a paradigm for understanding biology?
   1. I believe learning exercise physiology is imperative to understanding biology because it involves the animals and most importantly us. We study mice, monkeys and other animals in order to create medicine and figure out how the human body works. Learning this class, helps you understand what animals do to stay at their correct temperature, and normal bodily function. You also learn and understand the general makeup of why animals look the way they do, why birds have hollow bones, why we have so many bones, muscles and tendons. Also, the effects of exercise to our own bodies, understanding that can keep you healthy for longer, as well as your loved ones. This class will help you understand organisms on a fundamental level, and can help other people understand biology as a whole.
3. How can you use what you learned in previous upper-level courses to contribute to our exercise physiology discussions?
   1. In previous terms I have taken, Developmental Biology, Epigenetics, and Neurobiology and I feel that they have all helped build a foundation for this class. Each class spoke on a molecular level of how/why organisms are made the way they are. Now, this class I will learn the next level up, on a larger level of how organisms function. Developmental spoke a lot of how the body plan was set up, and I believe that will help my understanding of where the bones, ligaments and organs are set up and their function. I feel like Development was from fertilization to when the organism was born and this class will continue from when the organism was born to its maturation. I’ll be able to understand why certain animals are so small and what the advantages are to that, and why certain animals are formed differently than us and what are the results of those differences. For example I know that snakes have an extended torso in the body plan, and now I will learn how that extended torso helps or limits it’s mobility.