LACTATE POWER > Warm up for 10 minutes. Then do a 10- to 12-second all-out effort. Rest for 30 to 90 seconds, depending on your fitness level. Do six to 10 intervals, and end with a 10-minute cool-down.
A GOOD MEASURE > It seems simple, but cardio training is a precise science. Go too hard or too easy, do too much or too little, and you won’t get the results you want. Lab tests for performance indicators, such as VO2 max and lactate threshold, can help you nail the right workout every time. Plan to pay $150–$300 for the two tests. For testing locations in your area, visit skinet.com/vo2max.