I've been reading that "spot training" is ineffective. What is that? Do they mean all those leg lifts, crunches, and hip and butt exercises I've been killing myself doing (on top of walking on the treadmill) aren't doing me a bit of good?

The expression is "spot reducing," but you have the gist of things. The erroneous belief that doing an exercise for a particular body part will reduce the fat in that area is widely held. It's not that the exercises aren't doing you any good, they just aren't necessarily "burning" fat off of those areas.

Fat gets stored on our bodies in a certain order. That order is determined by gender and genetics. Most men store fat around their middles, which leads to "love handles" or beer bellies. Most women store fat on their hips and thighs, which leads to "saddlebags" (and other equally cute names). When we gain weight, we add fat to these areas before adding it elsewhere. As we lose weight, those places are the last to lose. That's one of the frustrations about losing weight: getting in shape and still having flabby arms, love handles, or whatever.

So your leg lifts are good for, well, lifting your leg. The muscle group you use when you do leg lifts is the abductors, the muscles of the outer hip. Along with your inner thigh muscles (adductors), they stabilize your legs while walking, running or cycling. They play a greater role in sports requiring lateral movement, such as tennis. They are smaller muscle groups than your quadriceps, hamstrings and glutes (front of the thigh, back of the thigh, and butt). When you do leg lifts, you're not using as great a percentage of your total leg-muscle fibers as you would if you were doing squats, for example.

If you do exercises that involve more muscle groups, you can do more work. More work requires more energy and more strength. Your body responds to forceful, repetitive work by increasing the size of your muscle fibers. When you have more muscle on your frame, you become leaner and you burn more calories, helping use up excess stored fat.

So continue walking on the treadmill (try some cycling and the stepping machine, too); you'll burn calories while doing those exercises. Do more exercises such as squats and lunges for your legs, bench presses for your chest, overhead presses for your shoulders and lat pull-downs for your back. These exercises will make you stronger and leaner faster. You can always do the body-sculpting exercises after you firm up all over.

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