How Long Does It Take to Get in Shape?

You want to be in better shape than you are right now. And you want to do so as fast as humanly possible, with no wasted time or effort. How long is it going to take… really?

How Fast Can You Get in Shape?

This is a tough question to answer, as the length of time it takes to get in shape depends to a large extent on where you’re starting from, what your genetics are like, how much time and effort you’re willing to put in, and what you mean by “in shape.”

• Do you want to run a Spartan race?
• Bench press 200 pounds?
• Lose 20 pounds of fat?
• Put on 10 pounds of muscle?

The answer to how long it takes to get in shape will vary for each one of those goals.

What’s more, no two people respond in exactly the same way to an identical program of diet and exercise.

Some folks, for example, will see larger gains in size and strength than others, even if they’re all eating and lifting the same.

You tend to see fast, medium and slow responders to most diet and training programs, which makes it notoriously difficult to predict exactly how your body will respond.

However, I will try to put some numbers on two of the most common goals – losing fat and gaining muscle – so you have a rough idea what to expect in return for all the work you put in at the gym.

How Long Does It Take to Build Muscle?

When you start lifting weights, it’s normal to see your strength increase quickly in the first few weeks. However, not all of those strength gains are driven by an increase in muscle size. 

One of the main reasons for the rapid increase in strength is your nervous system doing a better job at recruiting the available fibers in a given muscle. 

Gains in strength will outstrip gains in size when you’re just starting out, and the fact you’re getting stronger doesn’t mean that muscle is being built at an equivalent rate. 

As far as gains in muscle size are concerned, it’s hard to put a definitive number on how quickly those gains will come, as muscle growth varies so much from person to person.

Stuart Phillips, Ph.D., who has put hundreds of subjects through studies on training and muscle growth at Canada’s McMaster University, says he never sees average gains exceeding about 0.5 pounds of muscle per week.

Which means that the average guy can expect to gain around six pounds of muscle in their first few months of training. Women can cut that number in half.

You can certainly gain weight at a faster rate, as the addition of fat will add a few more pounds (maybe a lot more depending on how relaxed you are with your diet). But if it’s just muscle growth you’re talking about, those numbers are roughly where the natural limits lie.

Why Some People Build Muscle More Quickly Than Others

It’s also worth pointing out that those numbers are an average, and not everyone gains muscle at the same speed. Some lucky folks put on muscle relatively quickly when they start lifting weights. For others, the results come much more slowly, even if they lift and eat the same.

The figure below comes from a study where a group of guys with a similar build, age, and training history lifted weights for 12 weeks [1, 2]. It shows the average gains in lean body mass (a reasonable proxy for muscle mass) in both the high and low responders to resistance training.

When the researchers looked at the results of the men who built the most muscle and those who built the least muscle, they found roughly four times greater gains in muscle in the fast versus the slow responders.

To put it another way, you and a friend of a similar build could follow exactly the same training program and diet for the next six months.

But individual variations in the rate of muscular growth mean that he might end up gaining twice as much muscle as you do.

Research also shows a wide range of strength gains even in people following identical training programs [3].

Subjects were grouped into fast (those who made greater than 20% strength gains), medium (10-19% gains) and slow responders (less than 10% gains).

There was an average increase in strength of 29% for fast responders, 14% for medium responders and 3% for the slow responders.

In other words, some people respond extremely well to strength training. Some will get “good but not great” results. Others will respond a lot more slowly.

RELATED: How Long Does It Take to Build Muscle? What the Science Says

How Long Does It Take to Lose Fat?

How long it takes to lose fat depends largely on the amount of fat you have to lose in the first place. 

Someone who is very fat (think your typical Biggest Loser contestant) will be able to lose fat very quickly when they start dieting – several pounds of fat per week in some cases.

But over time, this is going to slow down. 

You might start out losing a couple of pounds a week. As you get leaner, this is going to slow down to a pound a week, then eventually a pound every other week.

In one study, researchers took a group of overweight and unfit men, and got them to train with weights three days a week [4]. On top of that, the men also did 30 minutes of cycling or walking in the same workout.

After 14 weeks, they lost an average of 16 pounds of fat. That’s a little more than one pound of fat lost per week, which is a solid goal to aim for.

If you drop 12 pounds of fat over a period of three months, you’ve done well.

You can certainly lose weight more quickly, particularly in the early stages of dieting, as some of that lost weight will come from water and glycogen stored in the body. 

But if you’re just talking about body fat, and assuming you’re not following an extremely low-calorie diet, one pound of fat loss per week is a realistic goal to aim for.

RELATED: What 15 Studies Say About How to Lose Fat Without Losing Muscle

The Law of Diminishing Returns

The more unfit and out of shape you are, the quicker the results will come. The fitter, stronger and more muscular you get, the more difficult it gets to make the same gains.

In other words, the first 10 pounds of muscle might come in 12 months or less. The next 10 pounds might take twice as long. Adding another ten pounds might happen a lot more slowly, over a period of several years.

For someone who is lean, fit and strong, gaining muscle and losing fat requires a significant chunk of time, effort and sweat. But if you’re currently fat and weak, you’ll be able to make progress a lot more quickly.

Think of it like this…

Imagine that you’re standing in a room.

There is a picture on the wall in front of you.

The picture is one of you, but with 20 pounds less fat, 10 pounds more muscle, or whatever result it is that you want.

Every step you take moves you closer to that goal.

Around your waist is a large rubber band, which is attached to the wall behind you. The band has plenty of slack in it.

You start walking towards the result you want.

At first, progress is relatively easy.

But with each step, the band becomes progressively tighter.

As you move closer to your goal, taking the next step becomes more and more difficult.

And so it is with getting in shape.

If, for example, you gained 15 pounds of muscle during your first year of training, you’re not going to do the same again in year two.

Expecting to make progress at the same rate forever is an expectation that ignores physical reality.

There’s going to be a large gap between the results you expect and the results you actually get.

You’ll feel disappointed… frustrated… and it won’t be too long before you want to throw in the towel.

In short, the fitter, stronger, or leaner you get, the harder you’ll find it to continue getting fitter, stronger or leaner.

If you’re currently fat and weak, you’ll see relatively fast results before the law of diminishing returns kicks in. Everything happens a lot more quickly when you’re just starting out. The longer you’ve been training, the harder you have to work for smaller, less frequent gains.