My favorite part about Exercise Physiology was learning about the immune system. I generally find this system of the body most fascinating because of the amount of different pieces that come together for the same goal, fighting against pathogens. I enjoyed learning about the immune system in this class because it capitalized on my ability to learn about my research topic, “Short and Long Term Effects of Anabolic Steroids”, in both a positive and negative manner. From a positive aspect, in class we talked about how inflammation is a process where white blood cells and chemicals protect the body against infection from bacteria and viruses . We also discussed how there are certain diseases, like autoimmune diseases, where the body doesn’t function properly and is overactive which can cause inflammation to work against the body’s own tissues and cause tissue damage. This related to my topic very well as it turned out that steroids can reduce the production of inflammatory chemicals in order to minimize tissue damage. From a negative aspect, we discussed in class the idea of the “Open Window Theory”, which talks about the idea of exercise induced immune system suppression, causing the body to be more susceptible to infection and diseases. In regards to my topic it was interesting as steroids that are used by powerlifters and body lifters can be dangerous because during post exercise they are already being affected by the open window theory. But on top of that, because of the suppression of inflammatory response of the immune system due to steroids, it can lead to higher cases of sickness and being prone to more infections. These two ideas really allowed me to differentiate between the positive and negative impacts of steroids.
In honor of a lot of topics discussed in the Endure book, the article I found was on the idea of endurance and testing to see how far the body could endure gruesome physical activities on a metabolic scale. In endurance challenges such as the Ironman triathlon or the Tour de France bicycle race, everyone has the same maximum level of exertion that they can maintain throughout the physical challenge. They concluded that in grueling physical activities that last for days, weeks and months, humans can only burn calories at 2.5 times their resting metabolic rate and not even the fastest ultra-marathoners can best that limit. One of the main reasons why is because above the limit of 2.5 times a person’s resting metabolic rate, the body begins to feed on itself to obtain the additional calories needed to function. In addition the limit may have to do with digestive capability of the gut. There’s a limit to how many calories our guts can effectively absorb per day and it’s why just eating more won’t improve endurance right away. From these findings from previous studies, these are some of the factors that up until now, defined what exactly is possible for humans in regards to endurance. In this study, the researchers measured daily calories burned by athletes who ran six marathons a week for five months as part of the 2015 Race Across the USA, which stretched 3,000 miles from California to Washington, D.C. They also looked at other ways to measure endurance through 100-mile trail races and pregnancy. What they found was that the mega marathon runners burned 600 fewer calories a day than expected suggesting that the body can lower down metabolism to keep the body going and prevent you from burning up all of your fuel sources. In addition, they also found that the maximum sustainable energy expenditure in endurance athletes was only slightly more than women’s metabolic rates during pregnancy suggesting that there the limits that prevent Ironaman triathletes from breaking speed records could be related to the same that keeps babies from growing too big in wombs. I thought this article was interesting as it gave another example of just how limiting the human body is across varying groups of people. Something I wish they spoke about was the manner at which the study was conducted. They could have looked at the effect that competitive drive played a role in the endurance. Perhaps another group could have compared how going head to head with other individuals affected endurance compared to doing the trial by yourself. I would have liked to see more of this because although there are physiological limits stopping us from reaching certain records, there are also neurological factors that can cause us to either break these limits or hinder our ability by telling us we are tired when the body may still have a little bit more energy to continue on. These topics are discussed in the Endure book such as in the section regarding belief and ones ability to believe they can surpass someone in a race as opposed to just running against yourself.
My presentation topic will be the impact of steroids on performance and how this affects the skeletal muscle system short term and long term. This topic interests me because throughout my high school athletic career I did have some teammates and peers who took on using steroids (some more serious than others), and even to this day I still hear about some who take steroids at the collegiate level. Although I know that I made the right decision to not take these substances in high school, I am still curious as to how they exactly work and the effect that it can have on an individual. I know that not all steroids are bad and I believe that part of the reason they are viewed so negatively in the world of sports is because a lot of people are not knowledgeable about this issue. Seeing as to the fact that we have a lot of athletes in the class who may come from athletic backgrounds, I am sure it would interest them to inquire more information about how these substances work in the sports world they are a part of.
I will be focusing mainly on anabolic steroids as that is the more common one used by athletes. So far I have discovered that these steroids act to increase muscle mass and strength. In addition, the main anabolic steroid hormone produced by the body is testosterone. Testosterone has two main effects on the body. Anabolic effects which promote muscle building and androgenic effects that are responsible for male traits, such as facial hair and a deeper voice. I will be focusing mainly on steroids closely related to testosterone as they work to mimic the way that it works in the body, triggering protein synthesis which in turn builds more muscle and effects performance. I still need to conduct more research to answer the other parts of my question.
Lactic accumulation in muscle cells and whether or not it is beneficial or detrimental has been a topic of discussion for a long time. In Lamb’s article “Point:Counterpoint: Lactic acid accumulation is an advantage/disadvantage during muscle activity,” it discusses how several tests involving exercise were used to determine why lactic accumulation is a disadvantage. In an experiment involving intense arm exercise lactate concentration in the blood was elevated and in turn led to an observed reduction in the performance of leg exercise. However this is not just limited to certain parts of the body as studies that tested many parts of the body showed similar results. In a knee-exterior exercise the time until exhaustion was 3.5 min while compared to 4.7 min in the normal condition has been used to elevate the lactate concentration in the blood and all have observed a reduction in performance of leg exercise (1).
In another study, when maximum voluntary contraction (MVC) was at 50% it caused muscle fatigue and exhibited the highest elevations in blood lactate concentration, blood pressure and respiratory exchange ratio (2). In addition, blood lactate levels were significant contributors to brain blood flow because it was observed in the standard partial regression coefficients for blood lactate, which showed the degree of effect was p=0.75, suggesting that lactate level affected brain blood flow. Thus, blood lactate concentration during exercise exhibited the greatest increase at this intensity. This study also found that lactate played a role in the sensation of pain and that muscle pain is associated with reduced performance. More studies need to be taken to further prove these ideas but it does seem to be a notion that lactate production is associated with pain, making it disadvantageous.
- Lamb G.D., Stephenson D.G, Bangsbo J., and Juel C. (2006). Point:Counterpoint: Lactic acid accumulation is an advantage/disadvantage during muscle activity. Journal of Applied Physiology. 100:1410-1414
1) Explain your favorite or most cherished athletic/exercise accomplishment
My most cherished athletic moment was scoring a hat trick in lacrosse during my senior year of high school. A hat trick is when someone scores three goals in one game. Lacrosse is something I have been passionate about ever since starting it in the 7th grade. Out of the three sports I did during high school (basketball, football, and lacrosse) lacrosse was the one that that I always seemed to perform at best. We were playing at home against one of our conference rivals, Christian Brother’s Academy. I was the 3rd leading scorer on my team averaging about 2 goals a game. Our two best players were out with injuries so naturally my team looked to me to step up and score more, which I did end up doing. I scored my first two goals very quickly in the earlier periods and ended up scoring my last goal on a buzzer beating game tieing goal to send my team to overtime. We ended up winning the game in overtime.
2) Why do you think exercise physiology can serve as a paradigm for understanding biology?
Exercise physiology can act as a paradigm for understanding biology because a lot of what we will speak about in class will be based on how our body acts in certain conditions and what pathways or mechanisms affects the way that we act as well. It is important to be able to understand how the body works during exercise or any form of physical activity so you know the ways not to harm yourself and allow your body to perform in the best way it possibly can.
3) How can you use what you learned in previous upper-level courses (BIO, BNG, NS, BioChem, CHM, PHYS, or ?) to contribute to our exercise physiology discussions
I have taken a lot of upper level course that I believe will contribute to my understanding and discussions in this class. I have take organic chemistry and a lot of what we will be discussing is how certain hormones, proteins and other functional groups impact the way our body functions in exercise. I have also taken behavioral neuroscience and neurobiology, and both courses talk in detail about how all of the pathways in our bodies work to send out certain signals which help our body to function on a daily basis. These classes and others will help with my ability to participate in exercise physiology discussions.