You may know from my previous blog post on cardio that low to moderate-intensity cardio is a fat-burning activity, whereas HIIT and weights typically are not.

HIIT and weights are anaerobic activity, which means your body uses glycogen (carbs) as the main fuel source, not fat.

Cardio is an aerobic activity, which means your body uses glycogen (carbs) and fat as the main fuel source. When you do cardio your body gets into the fat-burning zone.

Note that HIIT and weights typically do not burn fat.

CARDIO (longer duration steady state exercise) –> AEROBIC–> BURNS FAT

HIIT (short bursts of high-intensity exercise) –> ANAEROBIC–> BURNS GLYCOGEN

SO WHY DO WE STILL NEED TO DO HIIT THEN?

HIIT is great because it increases your general cardiovascular fitness and your anaerobic threshold. This means that during exercise your body will remain in the aerobic (fat-burning) zone for longer, before switching to the anaerobic pathway.

The result? You can exercise for longer and at a higher intensity and still burn fat.

HOW TO DO HIIT EFFECTIVELY FOR FAT BURNING

The best fat-burning HIIT workout exercise is interval running. It is similar to sprinting but they are not quite the same. Let me explain :)

SPRINTING

If you are sprinting for 15-30 seconds at your absolute fastest speed, with a 30-second rest, your body is using the anaerobic pathway and is predominantly glycogen. 

Sprinting is a great workout. It engages your muscles more and focuses on muscular power. So you’re likely to build more muscles with sprinting than with just steady-state running.

If you don’t mind a more muscular look, then this is probably a great style of workout for you. But if you prefer a more lean and slim look, it might be best to avoid this type of training and focus on interval running instead.

INTERVAL RUNNING

If you are running at a fast but not maximum speed for 90 seconds to 2 minutes, your body will most likely remain in the aerobic zone for the majority of the time. This means you’ll continue to burn fat.

The fitter you are, the longer your body will remain in the aerobic (fat burning) zone before switching to anaerobic.

The result? You’ll burn more fat!

HOW TO GET LEAN LEGS BY USING HIIT – FAT BURNING HIIT

Interval running is the best type of HIIT for fat-burning and achieving a skinny legs for me :) I started to use this technique a couple of years ago when I was training for a triathlon.

I used fast-paced interval runs (not a full-on sprint) to help me develop my cardio fitness faster. And it definitely helped with my cardio fitness, as I expected. But I also noticed something else.

You see, I’m a mesomorph body type and I can build muscle fairly quickly, especially on my legs. And interval running actually helped me lean out my legs. You can read my blog where I talked about how Cardio can help in getting those skinny legs :)

SHOULD I TRY INTERVAL RUNNING?

If your goal is to get slim and lean legs without bulkiness and you want to achieve it a bit faster, interval running could work very well for you. 

This type of workout will help you burn a LOT of calories and is great if you want to challenge yourself.

But there are some things you should take into consideration:

YOUR BODY TYPE

Interval running may not be the best choice for endomorphs. It may cause their legs to bulk up.

If you are not sure about your body type, I have a special body type quiz you can take. It will help you learn your body type in just two minutes, it’s completely free and you will get tips on how to train and eat specifically for your body type :)

WANT TO KNOW YOUR BODY TYPE?

• Complete the quiz in 2 minutes
  
• It’S free
• You will get 3 nutrition and workout tips for your body type

START THE QUIZ NOW

YOUR FITNESS LEVEL

If you are already in pretty good shape and you would like to do it, I would do this once per week at a maximum.

I also need to warn you that it is really difficult. If you are not already fit, I would not recommend it.

But if you are sure you want to try interval running as your fat-burning HIIT routine, don’t do a proper sprint. It’s supposed to be more of a fast-paced interval run. 

This shouldn’t cause bulkiness like short and intense sprints usually do.

Also, make sure you do it on a flat surface. Hill runs are great but you will build more muscle that way.

HOW TO COMPLETE THE INTERVAL RUNNING CIRCUIT

• 5-minute warm-up walk at 6-7km/hr
• 400m run at around 14km/hr (takes about 1 min 50 secs)
• 60-second walk at 6km/hr
• Repeat as many times as you can. If you’re a beginner, aim for 3-5 rounds. If you’re advanced, aim for 8-10 rounds.
• 15 minute cool down walk at 6-7km/hr

NOTE: You do not have to do your 400m run at 14km/hr. However, it must be at a pace that is fast and quite difficult for you to maintain for 2 minutes. After the 2 minutes, you should be in desperate need of a rest. Choose a pace that suits you best. :)

HOW TO DO FAT BURNING HIIT IF YOU DON’T WANT/CAN’T RUN

You can apply this same principle to other forms of gym equipment such as the bike or cross trainer/elliptical even though I have to say that those are not as great as interval running.

But if you can’t run for some reason, here are your alternatives.

INTERVAL TRAINING ON A BIKE OR CROSS TRAINER/ELLIPTICAL

Cycling can cause bulkiness, especially if you are an endomorph body type. And even if you are a mesomorph I would still do it probably once per week.

As for the cross trainer/elliptical, I don’t think that it will really cause bulkiness.

This machine engages your quads so you can gain more leg muscle than you would like. But it’s not the style of workout that will necessarily cause your legs to really bulk up.

If you can’t do interval running for some reason, the cross trainer is the next best thing.

HOW TO COMPLETE THE CIRCUIT 

• Exercise at a medium to high intensity for 90 seconds to 2 minutes.
• Have a rest or reduce the intensity for 60 seconds. I recommend a 60-second break, but if you need 90 seconds, that’s OK. 
• Repeat as many times as you can.
• This does not need to be done at the gym either. You could cycle outside rather than on the treadmill or bike.

CONCLUSION

Getting lean or skinny and toned legs with HIIT is not only super effective but also adaptable to different fitness levels and preferences. By focusing on interval running instead of full-on sprints, you can stay in the fat-burning zone longer, making it a fantastic method for slimming down without bulking up. HIIT can be challenging, but the rewards for your cardiovascular fitness and fat loss are absolutely worth it!

LEAN LEGS PROGRAM 1

If you would like a more specific workout program to target fat loss on your legs and to build lean muscle without getting bulky, check out my Lean Legs Program 1. 

My program contains an 8-week workout plan. But if you grab the Next Level You Package, you’ll also get a nutrition plan for each of the three body types.

Love Rachael xx

P.S. Read this blog post for a body-weight HIIT circuit that won’t bulk up your legs.

BEFORE AND AFTER PIC OF OUR COMMUNITY MEMBER

GET THIS PROGRAM

The post How To Get Skinny Legs: Fat Burning HIIT Workouts appeared first on Rachael Attard.