Family wants to do a sprint triathlon

My family is a very competitive one.

The main thing everyone likes to compete on is fitness goals. Everybody loves playing a game of volleyball or soccer and keeping points. Sometimes we do rope courses or other fitness courses to compete with one another. The most recent thing is that everyone in the family wants to do a sprint triathlon. This is where you swim, bike and run. The stats on this are you swim for .4, 12.5 mile bike ride and a final 3 mile run. I am not worried at all about swimming .4 miles. I am a good swimmer and I feel I could go forever. I think then immediately jumping on a bike will stink, but it is a doable amount. Honestly the thing I am most worried about is the run. Swimming, biking and then ending with a run sounds horrible. I will be wet, sluggish and tired. Also, I am not a confident runner. I average about 10 minute miles I am so bad. I know that my strides are small and I always get a side cramp. I think with me being tired going into the run, I will really stink. I don’t want my family to laugh at my sprint triathlon scores. I need to practice up and get my body in shape. I have gotten a gym membership and have been working on the different portions. Some days I just swim laps at the pool. Other days I do sit down and stand up bikes. Most days I am running on the treadmill at different inclines.
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