It’s likely no other purchase will improve your bike speed as much as quality coaching. If possible, find a coach in your area (Usatriathlon.org has listings on a map), or consider a reputable online coaching service such as D3multisport.com. The new athlete-coach matching program on Trainingpeaks.com is also a helpful resource.
Tip: If a coach is out of your budget, a heart rate monitor is an effective tool to take out some of the subjectivity so you can plan effective training based on actual workout performance.
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