DAY 2: Do 10 minutes of circuit training and a 30-minute run with short bursts of speed work using stairs or by increasing the incline on your treadmill. Run your first 20 minutes at an easy pace. At minute 21 do as many flights of stairs as you can and then walk down. (If you're on a treadmill, adjust the incline accordingly.) Return to your easy pace for two minutes and then repeat the cycle until you've finished 30 minutes of running. (Treadmillers: You can achieve this same effect by increasing the incline every 15 seconds until you reach your max, then revert to the starting pace.)

DAY 3: Do 10 minutes of circuit training and a 30-minute run on a treadmill or outside. (Treadmillers: Increase your speed by 5% and adjust incline to 2%.) Start with an easy run for 5 minutes. Run minute 6 and 7 at race pace, then revert to your comfortable pace for 5 minutes. Keep up this rotation for 30 minutes.

DAY 4: Do 10 minutes of circuit training and 30 minutes of cross-training. In other words, do a half-hour of cardio that isn't running.

DAY 5: Head outside or hop on the treadmill. Get ready to kick it up a notch this week. (Treadmillers: Increase your speed by 5% and adjust incline to 2%.) Start with an easy run for 5 minutes. Run minute 6 and 7 at race pace, then revert to your comfortable pace for 5 minutes. Keep up this rotation for 3 miles or 30 minutes.

DAY 6: Head outside or hop on the treadmill and run for 4 miles or 40 minutes.

DAY 7: If you haven't started practicing yoga, what are you waiting for? Core strength and flexibility are essential to staying injury-free.

MORE TIPS

MASTER YOUR MECHANICS
Loosen up! Periodically "shake it out"—your shoulders and arms, that is. Relaxing your shoulders will save a lot of energy in the long run.

COOL DOWN
Follow your run with a stretching routine to boost recovery and flexibility. Stretch your hamstrings, quads, hips, groin, butt, calves, shoulders, abs, and chest. Use resistance tubing or a towel to increase the intensity. To see videos for all these stretches click here.

FUEL UP
Post workout, drink up! Don't just rely on plain water. Replace the minerals such as potassium and sodium lost through sweat with water containing electrolytes and good energy bars with complex carbs. And 30 minutes post-workout down a protein shake or an egg white omelet. Why? Protein feeds your muscles, speeds recovery, and helps reduce soreness and muscle breakdown.

BREAKTHROUGH
Push yourself to try a new combination of cardio. 2,500 meters on rowing machine plus 15 minutes on a VersaClimber plus 15 minutes on Upper Body Ergometer equals an amazing cardio workout!

CELEBRATE SMALL VICTORIES
Write down your small victories this week.

WEEK 3

SCHEDULE YOUR WORKOUTS
Mark your calendar for five workouts this week. Make it a morning ritual so that none of the day's events prevent you from accomplishing your goal.—David Kirsch

CIRCUIT TRAINING
Warm up every day with circuit training. Choose from the following and be sure to mix it up each day:

1. 15 Squat Thrusts
2. 30 sec. Mountain Climbers
3. 30 sec. Shadow Boxing
4. 15 Walking Lunges
5. 15 One-Legged Squats
6. 15 Jumping Lunges
7. 15-20 Spider-Man Push-ups
8. 15-20 Double Crunches
9. 30 sec. Wall Sit

DAY 1: Do 10 minutes of circuit training and 30 minutes of running outside or on the treadmill. Then crank up the intensity. (Treadmillers: Increase your speed by another 5%.) Run 5 minutes at an easy pace, then run minutes 6 and 7 at slightly faster than race pace, then revert to your easy pace for 5 minutes. Keep up this rotation for 30 minutes.

DAY 2: Do 10 minutes of circuit training and then head outside or hop on the treadmill and run for 40 minutes.

DAY 3: Do 10 minutes of circuit training and then run for 30 minutes. Run 15 minutes at an easy pace. Starting at minute 16, do as many flights of stairs as you can and then walk down. Return to your easy pace for 2 minutes, then repeat the stair climb two more times until you've been at it for 3 miles or 30 minutes. (Treadmillers: You can achieve the same effect by increasing the incline every 15 seconds until you reach your max, then reverting to starting pace.)

DAY 4: Do 10 minutes of circuit training and then 30 minutes of cross-training, i.e., cardio that isn't running. This will help you build strength and endurance.

DAY 5: Do 10 minutes of cross-training and then hop on the treadmill or get outside for a 40-minute run.

DAY 6: Start off with 10 minutes of circuit training of a 4-mile run (or 40 min.) with Fartlek training = 50 min. Do 10 minutes of circuit training and then hop on the treadmill or head outside for a 40-minute run. Again, crank up the intensity. (Treadmillers: Increase your speed by another 5%.) Run 5 minutes at an easy pace, then run minutes 6 and 7 at a slightly faster than race pace, then revert to your easy pace for 5 minutes. Keep up this rotation until you've been running for 40 minutes.

DAY 7: Time to take a day off. Rest and restore with stretching, walking, or yoga.

MORE TIPS

MASTER YOUR MECHANICS
Remember to keep your chest out, your shoulders back, and your head upright with a slight forward lean. Run with confidence.

COOL DOWN
Follow your run with a stretching routine to boost recovery and flexibility. Stretch your hamstrings, quads, hips, groin, butt, calves, shoulders, abs, and chest. Use resistance tubing or a towel to increase the intensity. To see videos for all these stretches, click here.