When people hear about HIIT, they tend to think it's all about jacking up the heart rate with stuff like burpees, mountain climbers and jump squats. While that's certainly part of it, getting your heart rate high is not the be-all and end-all of fitness, whether you’re in it for fat loss, performance, or just overall health.

Resistance training—things like weighted squats, overhead presses, deadlifts, push-ups and pull-ups—which is also known as strength training, is just as important. Here’s why:

Strength is the foundation of any kind of movement

Let’s use mountain climbers as an example. If you don't have enough upper body and core strength, you won’t be able to hold plank position with optimum technique—which means you won’t be able to get the most out of this exercise.

If we extrapolate this concept further, in order to do a burpee with a jump safely, you need plenty of leg strength for exploding off the ground and absorbing the impact upon landing. In short, in order to earn a resilient body that can perform high-yield athletic movements, first you need to get strong.

Strength training has excellent metabolic effects

Yes, you read that right. It’s not just the burpees that are good for getting that lean, firm, athletic look—strength training helps too by creating an environment in the body that is conducive for fat burning. Simply put, strength training helps build lean muscle (not bulk), and having more lean muscle means your resting metabolic rate is higher than it used to be.

As you get stronger, you also start to be able to do more difficult movements, lift more weight, and do more reps. All of this means you burn more calories during each workout. As you can imagine, doing 10 squats with an 8kg kettlebell requires more energy than doing the 10 squats without additional weight. When you dig yourself a deeper ‘hole’ with a mix of both strength and cardio, your body has to work to recover from that over the next 16-48 hours, which is the afterburn effect.

Yes, doing the appropriate forms of resistance training will also give you an afterburn effect, just in a different way. Think about it like this: with strength training, your lungs and heart aren’t on fire, but your muscles are. Different types of burn, but both equally important for getting lean.

Strength training builds and maintains bone density

While research has shown that adults who don’t perform resistance training may experience a 1-3% reduction in bone mineral density every year, the science is clear on how to mitigate this. Resistance training strengthens bones, muscles and connective tissue, which increases overall resilience, decreases the chance of injuries, and can prevent osteoporosis in the long run. As you age, it may also help with movement control, speed, functional abilities and overall physical performance.

Strength training will increase your general quality of life

Yes, getting strong means you’ll have to work harder while you’re exercising, but this will result in having an easier time of it in all other aspects of your life. From carrying your groceries to playing with your kids and climbing over walls—all these things will be easier to do if you’ve built some functional strength.

On top of all this, there’s a wealth of research on other benefits of strength training, like how it helps improve cardiovascular health, mental health and cognitive abilities, while decreasing risk of type 2 diabetes, amongst other things. Strength training is magic.

Key takeaways

• Burpees and mountain climbers are great, but strength training is your friend, too. Don’t be shy about lifting weight, and don’t be afraid to push yourself on stuff like weighted squats, deadlifts, overhead presses, push-ups and pull-ups. When it starts feeling like too much, simply drop to a lower weight or an easier exercise.
• Strength training is important for increasing your metabolic rate, and the overall caloric burn you can achieve in each workout in the long term. It will also help with your bone density as you age, and keep you more resilient against injuries.
• Focus on form and engagement. Yes, it’s important to do the hard stuff, but think about what it feels like when you’re doing the hard stuff. For example, during push-ups, you’re not just working on your chest and arms—it’s a full body exercise that starts with core strength. This is why we tell you to keep your abs and butt tight!