"Our distant ancestors had a word for exercise: life."
- The Hungry Brain, Stephan Guyenet, Ph.D.
Our bodies are designed for movement!
That's why we have muscles: to move our legs, arms and body around. Until modern times, constant daily movement was a part of everyday life for humanity. Our ancient ancestors got a LOT of exercise trying to obtain food, shelter and clothing.
In contrast, our modern lives are very sedentary (vehicles, smartphones, Netflix, desk jobs). This kind of lifestyle (lack of movement) is not something your body was engineered to handle. It literally makes things go haywire. Long term lack of exercise is the cause of many, many health problems.
Getting regular physical activity is the solution (even the cure in some cases) for many diseases and or mental issues. If you want to be smarter, happier, and healthier... get plenty of exercise.
In terms of weight control, is it any wonder that combining lack of movement with unlimited easy access to high-calorie "food with no brakes" which is the case with modern civilization today that we end up consuming excess calories as fat that is never burned off?
Many people try to argue against exercise and will do anything to find an excuse not to do it. They'll focus on any shred of evidence they can find regarding how you can get injured, or how exercise isn't good for your knees, your heart, and so forth.
The fact is, if you want anything close to the quality of life you were born to have and so richly deserve, you MUST move your body!
So the health benefits of getting regular physical activity are astounding.
But it's role in actually LOSING weight is a different question...
Surprisingly, a long string of scientific studies has shown that exercise in general has a small effect on the amount of weight lost. In general, most people -- including many fitness gurus -- over-emphasize the role of exercise and expect too much from it. When approached the right way, exercise plays a critical role in weight management.
What is the most powerful factor for losing weight? Your diet (calorie intake).
It's a matter of simple math and a dose of reality.
For example, we can easily consume 1000 calories in just a few minutes, but it takes a lot more effort and a lot more time to burn it off (at least 1.5 hours of jogging). For an average person to burn enough calories to lose a pound of fat (3,500 calories), they would have to jog for 5 or 6 hours straight. That's longer than it takes the average runner to complete a marathon! If you spread that across a week, it's 45 to 60 minutes of jogging per day. That kind of exercise may not seem like a huge deal to exercise gurus and fitness fanatics. But it's not necessarily realistic for beginners who are trying to lose weight.
As well, people tend to underestimate how many calories they are eating and overestimate how many calories they're burning through exercise, which only magnifies the chance of unrealistic expectations.
You also can't use exercise alone to get great muscle tone -- as the famous saying goes: "Abs are made in the kitchen!". In fact it's common for athletes to undergo a weight loss phase with only limited exercise, then go back to serious training after the weight loss diet is done. The body has a difficult time gaining strength and fitness and retaining high performance while in a calorie deficit (a catabolic state).
That said -- exercise has many benefits that can help you manage your weight. And never forget the quality of life benefits.
Individual benefits of exercise may vary, but here's a list of why exercise is highly recommended.
Prevent Weight Regain: This is probably the most important reason to get into the habit of regular exercise as soon as you can. A lot of research has shown that exercise plays a major role in preventing weight regain after losing weight. It does this in two ways. First, the extra calories burned help compensate for possible NEAT reduction (see metabolic adjustments). Second, exercise may help overcome your biological "lipostat" -- your internal fat monitor that wants you to regain the fat you've lost in order to stay at a certain weight.
Burn Calories: Exercise increases the number of calories you burn (Calories Out side of the Energy Balance Principle). Even though you tend to eat more when exercising regularly, studies show that for most people, the increased calorie intake is not enough to undo all the extra calories burned through exercise. In short, exercise tends to increase the calorie deficit and even if it's only a little, it helps.
Look Better (Body Composition): Exercisers during a diet tend to retain lean body mass (LBM) and lose more fat. Resistance exercise in particular is important. Even on a diet with adequate protein, exercise is good "LBM insurance" and assists in other ways.
Diet Adherence: For some people, exercise creates positive psychological motivation to stick to good eating. They think like this: "I worked out today and don't want to ruin it by eating badly." Or, "I need to eat nutritious food to fuel my body for my exercise goals." In other words regular exercise can increase your self-control on a diet (psychological/emotional strength).
Less Hunger: For many people, exercise can help keep hunger hormones in control (basically, you may feel less hunger or less out-of-control hunger)
Emotional Eating Control: Endorphins boost your mood and reduce anxiety which is great by itself, but it can help you avoid stress or emotional type eating
More Energy: Surprisingly, exercise tends to give you more energy (not less!). There's something about "getting the blood pumping" that increases energy for the rest of the day.
You Can Indulge More Often: It's also true that if you get enough exercise, you can "indulge" in your favorite foods more often than those who don't exercise. If you exercise enough, many people can eat a lot of calories without gaining weight. Some can eat as much as they want -- but it does take a lot of exercise to pull off that trick and shouldn't be expected to product weight loss. Typically this type of massive calorie burn is done through a cardiovascular-based sport like running or cycling where it becomes an enjoyable lifestyle choice for the participant.
Lose Weight: This is a bit of a contradiction to what we said earlier, but the fact is, if you exercise enough -- and ensure that you're eating enough healthy food to fuel your workouts -- you can gradually shed pounds over time. It's just that most people don't have the time or the self-discipline to do it. Weight loss through exercise often occurs with an endurance athlete in training who spends hours and hours training. What happens is they lose weight because their eating can't quite keep up with the huge calorie expenditure; as a result, they get gradually get leaner over the course of their training cycle.
It's possible to get too much exercise. See Too Much Exercise.
Exercise may not be helpful for you if you think this way: "I worked out today, I've earned extra food." and end up overcompensating with extra food. You do have some extra leeway but you can easily undo your calorie burn by overeating. After a hard work out is a good time to consume some protein for muscle repair, and carbs to restock glycogen ... but a modest amount is all you need.
For some beginners getting into an exercise program, exercise can trigger a blood glucose crash which stimulates hunger. If it occurs, realize that the effect diminishes after you've gotten through the initial phases.
The bottom line is that if exercise backfires for you (hunger, binges, overeating, desire to quit diet, weight loss plateau) then consider putting it off until you're in maintenance mode and not trying to actively lose weight.
One way or another it's worth figuring out how to make exercise work for you. And it doesn't have to be "hard" -- walking is probably the single best activity for anyone and the low intensity makes it much less likely to backfire or cause excess hunger. Also, after you pass the harder early stages of getting started, exercise becomes much easier to keep doing.
We know that it can be difficult to fit exercise into your schedule. But the way we approach it, there isn't any excuse to not get physical activity of some kind into your day.
Typically, the more fit you become, the easier it is to keep exercising. Why?
The best exercise is the one you can enjoy and stick with.
That said, let's talk about the two main categories of exercise. The first is aerobic or cardiovascular exercise, often called cardio for short. Some people refer to it as endurance exercise. The second type of exercise is resistance exercise, more often called weight training.
Aerobic exercise or cardio includes pretty much any activity that's performed continuously and repetitively for at least 20 minutes or more. It raises your heart rate during the length of the exercise -- hence the word "cardio". So we're talking about walking and running, of course, but also cycling, swimming, and step classes. Interval training is a type of aerobic exercise done in short but intense periods of time (seconds to minutes) followed by a rest -- read more in High-Intensity Interval Training.
Resistance exercise or weight training involves any activity where the muscles are used to work against some kind of resistance that you couldn't do for more than about a minute. So it's generally short bursts of strength against various amounts of weight, with brief rests in between. Often resistance exercise routines work through several different moves in order to make sure all muscle groups get worked out. Resistance exercise isn't limited to lifting weights at a gym. The weight of your own body can often provide enough resistance for effective exercise, and there are other inexpensive options as well. We'll talk more about equipment later.
You'll find that many weight loss gurus are also bodybuilders. Naturally, they claim weight lifting is the best way to lose fat. Likewise, you'll find gurus into running or cycling tell you that aerobic exercise is the only way to get into fat burning mode and lose weight. You'll also find people who insist that HIIT (high-intensity interval training) is superior to regular cardio.
The truth is, it's all good. Actually it is ideal to do both aerobic (cardio) and resistance exercise, if you can.
Both are beneficial for:
We'll say it again: any exercise you enjoy and can stick with is the best exercise. If you enjoy weight lifting, then do it. If you enjoy walking, running, cycling, swimming, tennis, whatever... then do that.
To help you get started:
As for interval training or HIIT, it's not ideal for beginners. Save it for later after you've gained some fitness and have been exercising regularly for several months (at least) such that you feel strong and confident in your routine and want to boost results.
Do some kind of physical activity every day if possible. See Move... any way you can.
Experts, as well as U.S. government guidelines, suggest getting at least 20 minutes of exercise a day, or 150 minutes per week.
We suggest working up to at least 60 minutes per day for weight-maintenance purposes. This can be low-intensity exercise like walking, or higher intensity as you get more fit... your choice.
In spite of what you might see on certain weight loss TV shows, exercise shouldn't actually hurt. Yes, pushing yourself gives fitness gains and faster breathing means you're burning off more calories. But especially in the beginning, focus on making physical activity a habit and not on the intensity or difficulty. Focus on making it enjoyable and rewarding enough that you do it every day! See Avoid #1 Mistake.
Intensity of Exercise
The higher the intensity, the more calories you are burning.
Low-intensity: Often called "conversational pace" because you can carry on a conversation without gasping for breath. It seems relatively easy. The vast majority of your aerobic (cardio) workouts like running, cycling, etc, should be at low-intensity -- even if you are highly trained. You might feel like you're not putting much effort into it at all. Your mind might start to wander. It's a pace you could easily maintain for longer than 20 minutes if you wanted to, because your slow-twitch fibers are replenishing their own energy supply as fast as you use it up.
High-intensity: You are typically breathing hard. It feels hard. Often these are interval type workouts. A high-intensity focused workout should only be done 1 - 2 times per week and the entire workout is often shorter. Avoid if you are a beginner or really out of shape, or on a rapid weight loss diet.
Weight lifting or weight training can also be done with high or low intensity but it's typically better to aim for greater effort, simply because each exercise is so short compared to aerobic activity. If a resistance exercise feels too easy it's probably not doing you a lot of good. Aim to challenge yourself by lifting more weight or doing more reps without making yourself miserable. There's a balance to be had. (See Avoid #1 Mistake.)