There are very different exercise protocols for building muscle size and building physical endurance. A study published in the International Journal of Sports Medicine suggests that a high amount of high-intensity exercise is most effective for increasing your capacity for exercise. Compared to low amounts of moderate and intense exercise, a lot of intense exercise promoted the greatest changes in markers of peak VO2.
What's that kind of workout look like? Consider Rick Schulze's weekend bike ride in preparation for the Race Across America (RAAM). He did the first 100 miles in less than 5 hours for an average pace of more than 20 MPH. The next 63 miles brought a brutal headwind that had most of his fellow cyclists managing just 5-8 MPH. Rick kept up a 13 MPH pace the rest of the way. Follow his training and mid-June race posts by Following @Team_ABB and @rickRAAM on Twitter.