To the Future...

     I am an exercise science graduate student. A former collegiate runner, I have a great love for and interest in the sport of running. Hopefully over the next few months I will begin to compile articles, thoughts, and opinions here in this blog.

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Pain in the Heel

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     In the last eight months, I've had some good stints of training. But for the most part, I've struggled to find consistency in running. I've taken time off - up to six weeks at a time. Two months ago, out of desperation - I got a cortisone injection in my heel. The cortisone worked really well for about six weeks, but as it wore off, I started having problems again. I've attempted three or four different comebacks, but each time, the same plantar fasciitis has come back.       When I started the year, I thought - Once I get over this foot pain, I'll have enough time to train for duathlon nationals. Then nationals came and went, and I didn't even make it to the starting line. I never thought the problem would persist so long that I start to question whether the World Championship (in September) could be in jeopardy.      And I never imagined something so small would have me questioning why I race in the first place. When you make sacrifices, you do s
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So you want to "burn fat?"

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Potential for Improving Endurance Performance through Substrate Conservation We know skeletal muscle needs ATP to contract and there are different pathways from which ATP can be synthesized. During endurance exercise, inevitably, some combination of glucose/glycogen and fatty acids will be used for substrate. Utilizing fatty acids for ATP synthesis could be beneficial for endurance athletes because humans have a virtually unlimited supply fatty acids, whereas stored carbohydrate is relatively limited - demonstrated below: 135,000 Cal from stored fat is roughly enough energy for a 65 kg person to run 2000 km (R. Margaria et al, 1963). A decreased reliance on carbohydrate and a subsequent increased reliance on fatty acids during exercise should help to "spare" muscle glycogen. Accepting the well documented theory that low muscle glycogen causes fatigue, one can see how glycogen sparing can potentially extend performance or allow for an acceleration late in a race. &q
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Lactate, Lactic Acid and Acidosis

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With respect to exercise, what do you think of when I say, “Lactic Acid?” Legs burning? Acidosis? Horrible stuff that slows me down? Lactic acid and lactate typically get a bad rap from athletes, but what if I said that rather than slowing you down, lactate production enables high-intensity exercise? Well, it does. Lactate vs. Lactic Acid      First, let’s discuss the compound itself. Lactate is not lactic acid. Lactate is a carboxylate, whereas lactic acid is a carboxylic acid. This means the carboxyl group of the lactate molecule is deprotonated and cannot contribute further to acidosis.  The image below shows the difference between the two molecule types.      The reason lactate does not exist as it's protonated acid form in the body is because the pKa of lactate is a low 3.9. This means is that in a solution with a pH higher than 3.9, the compound will exist as the deprotonated carboxylate, lactate.  As shown below, in Table I from Cairns ( 2006 ), the
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