What cardio for weight loss?

The major advantage of HIIT is the EPOC (Excess Post-exercise Oxygen Consumption) effect. Even after your workout, your metabolism remains activated for several hours, continuing to burn calories. It’s comparable to compound interest: you invest intense effort, and your body continues to “grow” this expenditure by burning even after the session. (In short, you keep gaining even after you stop sweating.)

A well-structured 20-minute workout can thus surpass a traditional cardio session in terms of total calorie expenditure. But beware: this type of effort requires a solid physical foundation and a true sense of regularity. The “miracle” 10-minute protocols seen online often don’t exceed 70% of maximum heart rate, limiting real fat-burning effects.

Low-intensity cardio (LISS)

LISS (Low-Intensity Steady State) maintains a moderate effort (60-70% of max heart rate) for 30 to 60 minutes. Inclined walking, breaststroke swimming, or cycling at a constant speed are concrete examples.

Its advantage lies in its ease of integration into a routine. You can listen to a podcast while walking, watch a video while cycling leisurely, or follow a session after a weight training session for active recovery. Unlike HIIT, it doesn’t exhaust your nervous system, allowing for regular practice without the risk of overtraining.

By burning primarily fats rather than carbohydrates, LISS preserves your muscle mass. A study shows it more effectively improves fat distribution in overweight individuals. However, it takes two to three times longer to reach a calorie expenditure equivalent to a HIIT session.

• Better suited for muscle preservation goals
• Ideal for active recoveries
• Accessible to all fitness levels
• Can be combined with other daily activities

Which cardio to choose according to your main goal?

Well, now that we know the two main forms of cardio, you’re probably wondering: which one is the most effective for you?

Let’s look at two typical profiles to better understand.

Goal #1: lose weight as quickly as possible

Want to lose weight quickly? High-intensity cardio (HIIT) is clearly your ally. By alternating phases of maximum effort and short recoveries, you can burn more calories in 20 minutes than in an hour of brisk walking.

But this efficiency has a downside: HIIT heavily taxes your nervous system and depletes your glycogen stores. Combining weight training and HIIT on the same day can impact your muscle progress… or not, depending on how you structure your sessions.

For example, in CrossFit, interval work is practiced, but sometimes with heavy loads. The result: you can gain muscle while burning fat. Why? Because caloric intake is often high alongside, and the exercises incorporate real muscle intensity. (It’s this subtle balance between load, nutrition, and recovery that makes all the difference.)

However, for someone starting out, this type of training will inevitably require a lot of energy. HIIT is demanding: it needs to be dosed, respected, and given time to work without rushing. (Better to go gradually than to burn out in the first week.)

Goal #2: lose fat while preserving muscle mass

So you understand, if HIIT allows you to lose weight very quickly. LISS offers a more gradual, slower loss, but often more stable over time. And above all, it allows you to better preserve your muscle mass. (Provided, as with HIIT, that you do some weight training alongside.)

Unlike HIIT, LISS doesn’t deplete your energy reserves. It helps you burn calories without tapping into your muscles, making it a perfect option to refine your silhouette without compromising your gains.

This type of effort also promotes active recovery between two more intense sessions. It helps you maintain good circulation, better oxygenation, and thus a steady progression. To track your progress and adjust your training, use our IMM calculator.

Between these two approaches, a compromise exists: combining 1 to 2 HIIT sessions with 2 to 3 LISS sessions. But this strategy is reserved for experienced practitioners. Beginners should favor LISS, a solid foundation for progressing without discouragement.

Remember the essential equation: a controlled caloric deficit remains key. Your best ally is the cardio you practice without frustration, week after week.

The mistake not to make: neglecting weight training

Well, we’ve talked a lot about cardio for weight loss, but one of the biggest mistakes many people make is neglecting weight training. It’s actually very simple to understand: the more muscle mass you have, the more energy your body needs to function daily.

Every 500 g of muscle burns about 100 kcal per day, at rest. Yes, you read that right: even without doing anything, your body consumes more if you’re muscular. Result: you might not necessarily lose more weight on the scale, but you’re leaner, more toned, because your metabolism works for you constantly.

The best way to preserve this muscle is simply to do weight training. Only doing cardio (especially LISS) will likely make you lose weight, but there’s a risk of looking like what’s called a skinny fat: thin, but without tone or visible muscle shape.

Every time you lift heavy weights, you create microtears in your muscles. These small tears are normal: your body then repairs them, and it’s precisely this process that makes the muscle grow and strengthen. And this repair work also consumes energy. (In other words, you’re still burning even after the session.)

So yes to cardio, but not without weight training. And conversely, weight training alone won’t be enough either: the two complement each other perfectly if your goal is to burn fat while sculpting your body.

Caloric deficit, more important than cardio

Cardio is just a lever. As its name suggests, in cardio there’s cardiac, so heart. Cardio is not primarily for weight loss, but to improve your heart health, boost your endurance, and support your body in its daily efforts.

Weight loss depends on one factor: burning more calories than you consume. Your body acts like a bank account: meals are deposits, energy expenditures are withdrawals. A deficit occurs when withdrawals exceed deposits, forcing the body to use its fat reserves. So you understand, whether in finances or for your diet, you’ll need to carefully analyze these expenses and deposits.

And to help you calculate all this without hassle, we have created a basal metabolism calculator which will be your initial tool to avoid starting off on the wrong foot.

So you understand, a too marked deficit (for example, 700 kcal less per day) can harm your body: fatigue, muscle loss, slowed metabolism… Opt instead for a moderate deficit (around 200 to 500 kcal per day), compatible with preserving your muscle mass. You can, for example, eliminate about 300 kcal daily through a mix of physical activity and slight dietary reduction. Cardio boosts expenditure, but without dietary control, its effects remain limited. A sustainable deficit is always better than a one-time extreme effort.

Perseverance always wins over intensity. A light but regular deficit is more effective than a drastic diet. A daily 30-minute walk, combined with balanced meals, already creates a sustainable deficit. A professional can then help you adjust your intake according to your metabolism.

So, you got it, cardio without a good diet for weight loss won’t do you… Hmm… much good.

The FAQ of “Why am I not losing weight despite doing cardio?”

Here’s a quick reminder of the main reasons why you might not be losing (or no longer losing) weight despite your cardio activity.

• Your calorie deficit is no longer ensured: your body has adapted to your efforts and is burning less energy than before. Solution: reevaluate your intake with a reliable method (like the Harris-Benedict equations) and introduce intensity variations in your sessions. Tip: alternate between low-intensity cardio (brisk walking) and short but intense sessions (sprints).
• You’re doing too much intense cardio: too many demanding sessions increase cortisol, the stress hormone, which promotes water retention and cravings. Solution: reduce the frequency a bit, and favor gentler activities like swimming or the elliptical, which limit muscle catabolism. Tip: keep 1 to 2 high-intensity sessions per week maximum.
• You’re stressed or lacking sleep: these two factors disrupt leptin⟧PH32⟧ (satiety) and ghrelin⟧PH34⟧ (hunger), which slows your results. Solution: sleep at least 7 to 8 hours per night and take active breaks (walking, stretching) to lower your cortisol levels. Tip: avoid screens an hour before sleeping.
• You’re neglecting strength training: without muscle stimulation, your metabolism slows down. Solution: add 2 to 3 strength training sessions per week (with dumbbells or bodyweight). Tip: focus on compound exercises like squats or pull-ups to maximize the afterburn effect.
• You’re confusing weight with body composition: the scale can be misleading. You might be losing fat while gaining muscle. Solution: rely on more concrete indicators (waist measurement, photos) and make sure to include protein in every meal.