Presentation Topic

I decided that my presentation topic would be on how exercise affects the immune system. We all learned that exercise does have an effect on the immune system, positive and/or negative, so I wanted to explore this and look into some research on this.

I will most likely look into Upper respiratory tack infections, or URTIs, for this presentation. Upper respiratory tract infections (URTIs) are the most common issues with the immune system that people get. URTIs include the common cold, sinusitis and tonsillitis. In the Martin et al. “Exercise and Respiratory Tract Viral Infections”, for example, they explore the relationship between the URTIs and the amount of exercise done by individuals. The research found a link between moderate, regular exercise and the reduced frequency of URTIs compared with an inactive state. There was also an increased risk of URTIs with excessive amounts of exercise.

This information is an example that exercise can influence a person’s vulnerability to infection. I found this research to be very interesting. It also agrees with the “open window” theory discussed in class, so I will most likely discuss this theory, and the research on it, as well.

Martin, Stephen A et al. “Exercise and respiratory tract viral infections.” Exercise and sport sciences reviews vol. 37,4 (2009): 157-64. doi:10.1097/JES.0b013e3181b7b57b

Negative Effects of Lactic Acid

The benefits of lactic acid accumulation in muscle cells are constantly debated, with some scientists claiming that the other side’s conclusions are the result of overstating their data. However, there is too much data proving that Lactic acid is disadvantageous to exercise performance. Its accumulation contributes to decreased performance in several ways.

In Lamb’s”Point:Counterpoint: Lactic acid accumulation is an advantage/disadvantage during muscle activity,” which is a response to an original paper, it is argued that elevated lactic acid in the blood causes declined performance, possibly because lactic acid reduces blood pH(1). Since Lactate lowered pH, once blood pH is raised, it has been shown to improve performance. These findings further supports the correlation of lactic acid with declined performance. A possible reason for these results could be due it being reported that disruption of calcium release and reloading of the sarcoplasmic reticulum which may be caused by lactate and H+ ions (1). Lactic acid and fatigue are correlated. Additionally, Lamb states that “there is a positive correlation” between Lactate efflux and performance (1).

It seems apparent that Lactic acid accumulation is disadvantageous, and Lamb appears to not approve of so much debate on the topic when evidence of its negative effects are so abundant. According to Lamb, “In the 1990s, we argued that high lactate and low muscle pH is not the primary cause of fatigue in humans, but it seems to contribute during intense exercise. As it currently stands, evidence is still lacking that this is not the case.”


  1. 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.

Blog Post #1

  1. I am not very athletic, so I don’t really have an athletic accomplishment to share. When I was younger, however, I was slightly more fond of outside activities. Even though I was a city kid, I would spend my summers in a suburban area, where it was more necessary to get entertainment outdoors. I enjoyed swimming, to the point that I could go everyday and never get bored. I also had an uncle who greatly enjoyed the outdoors, and who often took me out to experience nature. I would go hiking occasionally with my cousins during this time, or ride bikes. Although they aren’t exactly accomplishments, they are fond childhood memories relating to athletics.
  2. Exercise physiology would give more insight into the human body. Someone who isn’t very active will have a very different body type compared to a trained athlete. A runner will have a different body type compared to a football player. With exercise physiology, you learn what these differences are, how they developed,and why they can develop. Biology is about understanding the differences in living organisms, so I think this course will teach me about biological differences  in a field that I’m currently unfamiliar with.
  3. I previously took endocrinology, which could be helpful in understanding how some hormones are involved in exercise. I also took molecular genetics, which can also help to explain certain pathways and molecules that are common in physiology. It can also help to understand why some things are hereditary.