Self-assessment of online listening to podcast 1

I have listened to podcast "Study of college athletes finds exercise-induced asthma is common". The website address where I found this podcast is http://www.voanews.com/mediaassets/specialenglish/2007_10/Audio/mp3/se-sin-2456-digest-10-30-07.mp3 I found this listening very interesting, because speakers spoke about the winners of the Nobel Prize in medicine and about a health problem resulting from physical exercise. The level of English was intermediate and the rate of speaking was average. I think that the speakers accent was American. I listened this podcast only once because words was not difficult to understand. After listening I looked to a transcript. In this text was some words unknown for me: knockout, lung and induced, so I looked up the meaning of these words in a dictionary. I suppose that I am not completely prepared for my exam listening parer. I will improve my listening skills if I will listen to podcasts as often as possible, listen to my friends in English classes and after watching English films on TV looked up the meaning of unknown words in a dictionary.