Q: What should I eat before and after a 30- to 60-minute ride or run?

A: The main source of fuel for exercise comes in carbs. To keep trucking, start your day with oatmeal and berries. Fibre fills you up. Oatmeal, a slow-burning carb, will give you fuel for your cardio session. Eat a banana after: Potassium can help prevent muscle cramps. Even better, make a banana soy-protein shake to replenish energy and give your muscles what they need to recover.

Q: How do I find my fat-burning zone? And why should I try to use it?

A: Your fat-burning zone is the ideal level for building your aerobic endurance and, yes, burning fat. Find it by subtracting your age from 220 and then multiplying that number by 70 per cent. You can wear a heart rate monitor to watch your numbers or focus on exercising at a chitchat pace–that's one that allows you to carry on a conversation without getting totally winded. It takes at least 20 minutes to get into the zone, and the longer you go from there, the more fat you'll end up burning.

Q: My forearms cramp when I lift. What's going on?

A: The cramping could come from dehydration–so drink a lot and eat potassium-rich bananas to keep your muscles cramp-free. It also could be caused by weak forearms. To strengthen them do chinups and dumbbell biceps and wrist curls with light weights. No luck? See a doctor. A strained muscle or tendon in your forearm can radiate pain into your hand.

Q: I love to run in the morning, but my legs feel heavier than when I run later in the day. Any tips?

A: Yes: Keep it up. Studies show that if you keep going for 5 weeks, morning workouts can be habit-forming. As for heavy legs, don't just sprint from the sheets to the door. Get up 30 minutes before you leave the house to avoid what scientists call sleep inertia, the average time it takes your body's systems to wake up.

Q: Are rowing machines bad for your back?

A: Yes, if you're flailing like a loon. But if you use proper form, they're one of the most effective cardio machines–you can use up to 600 calories an hour. To avoid hyperextending your back, a common rowing injury, push with your legs rather than pulling with your back. And pace yourself: Warm up at about 8 to 10 rows per minute and work up to 20 to 30.