How often do you need to exercise to lose weight?

Technically, exercise is not necessary at all. It’s the net calories that you need to be concerned about.

If you’re losing inches, then you’re probably building muscle and redistributing the weight. If you continue the workout level and reduce caloric intake, you should start seeing some weight loss.

^^ what @syz said. Only to add that muscle mass will kick up your metabolism, which is what you want to do. Your body will burn calories more efficiently, and if you keep to your diet, you will be in good shape for the summer.

Well, if you are working with weights, you will be adding some muscle, which holds more water and so you will weigh a little more on the scale. If your gym has a way to measure your percent body fat, you might want to monitor that, and just measure, rather than obsess about your weight on the scale.

What @syz says is correct, it is net calories or energy that matters. If you are eating more calories not that you are exercising you might be coming out the same in the end. Counting calories is the best way to lose the weight. Approximately 3500 calores is 1 pound. So, if you eat 500 calories less a day, plus do your exercise, you should lose about 2 pounds a week. You need to figure out your goal weight and do the math for how many calories equals that weight. It has nothing to do with your height, basically a certain amount of calories taken in, adjust for exercise, equals a certain body weight. This is why when people stop their diets they gain the weight back, because they go back to eating for the higher body weight. I can dig up the equation if you are interested. But, again, you can figure for yourself by estimating what you eat and cutting calories.

You’re doing all the right things. Muscle weighs more than fat, so you’re building muscle and toning up. Don’t go by the scale so much. Look in the mirror and enjoy the results.

The short answer: more often than you eat.

By that I mean you have to exercise to burn more calories than you consume. There is no other way. And as @cazzie pointed out, “weight” isn’t the whole story. What makes up that weight is important.

I’d focus on inches instead of pounds. The weight of a person isn’t the best measurement of health, especially if you’re not obese It sounds like you have a good regimen going. Make sure to eat well, and don’t starve yourself. Keep it up!

I concur that exercise itself isn’t the be-all, end-all, nor is the scale. I spent most of my life at 155 pounds despite often eating like a horse partly due to a fast metabolism and partly due to the fact that my normal day-to-day activity was often strenuous enough to count as “exercise”. Now that I am older (my metabolism has slowed) and my days less active, I have to eat a bit better than I used to when I was younger though.

The key to achieving and maintaining a healthy weight is to balance your food intake and your energy expenditure, and it sounds like you have a healthy diet and exercise regiment. And don’t forget that the scale doesn’t tell the whole story.

Personally, when I want to lose weight, I always make sure I do some vigorous exercise after I eat something, especially if it’s a meal. But even if I ate a snack, I always exercise right after to burn off the calories I just took in. When you burn off any calories that you take in, and then some, you will lose weight. The most important time for me to exercise after I eat something is after dinner, in the evening. I make sure I don’t go to bed with a surplus load of calories. That will keep the weight on, or worse, add to it.

Exercise is important but reducing calories in is the real key to loosing weight.

Reduce your intake to 1200 calories and exercise 500 calories a day and you should get pretty close.

Try to mix up your cardio. One day run, another day box, another day swim or do spinning etc. Your body will burn more calories overall if you mix up your cardio and strength training plus if you closely watch your calories which you can do by keeping a food diary where you record everything you eat and drink so you can see where the extra calories are coming from and then will be able to make substitutions thus lowering your calorie intake.

I agree with @cazzie and @Facade – rather than setting a goal weight, try setting a goal jeans/dress size.

In order to lose weight, you need to have a calorie deficit. That means, to oversimplify, that you need to be using more energy than you’re consuming. Strength training is great for weight loss, but it needs to be done right—and there’s more to it than there might seem. I would suggest you stick to the cardio for now, at least for a couple weeks. The focus will help you. In addition, you need to be mindful of the kind of cardio you’re doing. If by “cardio” you mean “walking”, well, you probably won’t see much. That’s doubtful, so I imagine you’re doing something like the elliptical or exercise bike. These are okay, but they won’t tax your system that hard—which is one reason you can do them for an hour. Since it seems like you have an endomorphic body type (where it’s hard to take off weight), I think the key to achieving your goal in this case will be high-intensity exercise. It’s hard, it’s painful, and it works wonderfully and immediately. It also boosts your metabolism for days, facilitating weight loss. Do a Google search for HIIT (high-intensity interval training). HIIT can be done with nearly any kind of exercise.

@quarkquarkquark I was under the impression that strength training was good for taking off fat but often kept weight constant (or even added pounds) due to muscle. You may lose inches, but you may actually gain pounds.
As for cardio, you have to be pretty intense unless you plan to be there a while. Jogging may get the heartrate up a bit, but you need to jog for longer than you would need to sprint for the same benefits. There is a reason that I used to mountain bike (actually ride as opposed to a stationary exercise bike) as hard and fast as I did and often on hills as opposed to merely cruising around on level ground ;)

@jerv, it’s relatively hard for women to gain a substantial amount of muscle mass. Otherwise, you’re totally right. We want muscle! It’s nearly twice as dense as fat. Strength training doesn’t truly take off fat, it’s simply that an increase in muscle burns fat quicker.

Muscle and fat are two separate things. You can have huge strong muscles, but if you have a bunch of fat also, pretty much you will just look fat.