<p>I'm skeptical of all these programs. The intent of these programs is to make you look good. If you want to look good then its probably ok, hey who doesn't, but I question whether it does anything positive for an athlete to promote getting faster in your sport. I know people that do p90x, people I train with. How it effects your running I suppose is very specific to the individual. If you do p90x or any type of fs routine I wouldn't do it more than twice a week. That is if you are going to do swim/bike/and running the rest of the week. </p>
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<p>That said I do pylo routine twice a week and work on my core at least once a week, just because... i want to look good
But I build my speed by killing myself on the bike trainer and keeping my running up 4x a week with hard runs and hills and swimming with masters group. I think if anything these routines can help prevent injury and are good for those with bone density issues.</p>
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<p>That said I do pylo routine twice a week and work on my core at least once a week, just because... i want to look good