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Interval training vs. resistance training


1st Jan 2015 Wellbeing

Interval training vs. resistance training

Ask most people interested in fitness and they will tell you that people squat with heavy weights to get bigger and stronger muscles, while people who sprint do so to increase their athleticism, speed and endurance. Generally speaking, these statements are true, however, there is greater overlap between resistance training and interval training than this suggests.

Resistance training

Resistance training involves a movement in which one's muscles or groups of muscles are used to move a moderate to heavy weight for several repetitions. 


Resistance training stimulates Type IIb muscle fibres, which contributes to the development of lean muscle mass.

By having more lean muscle mass, a person will burn more calories per hour at a resting rate, than someone of the same weight with less muscle. When applied in different ways (such as with higher repetitions and shorter rest periods), it can also be an effective tool to increase endurance.

As well as this, resistance training itself heightens the trainee's metabolic rate for several hours after that person has finished exercising, and also increases bone density.


Using very heavy loads in resistance training can be dangerous and lead to injury, which can be very severe in some cases. If performed improperly, resistance training can lead to muscular imbalances and poor posture.

Also, if insufficient attention is given to rehabilitation exercises (like stretching) over time, resistance training can exacerbate feelings of tightness or tension in certain areas - common problems include lower back pain or reduced shoulder mobility. 


Interval training

Interval training (commonly known as HIIT) consists of performing an activity (such as sprinting or rowing) with great intensity for a short period of time (usually no greater than 30 seconds), followed by a period of low intensity activity or complete rest for another interval (usually 30-60 seconds). 


Interval training can improve glucose tolerance, reduce body fat, increase VO2 max (though this is still debated), and is more efficient than steady-state cardio, as it can improve both the aerobic and anaerobic systems to a great degree, despite HIIT workouts rarely exceeding 30 minutes.

HIIT also stimulates fast-twitch muscle fibres, and can therefore potentially contribute to muscle growth. 


Interval training is very easy to overdo, and like resistance training, the risk of injury is high. Sprinting, for example, can easily lead to pulled or torn muscles, so it is very important that you fully warm up before performing HIIT. Finally, it can cause extreme lactic acid build-up, which can be painful, or vomiting. 

For an optimally fit, healthy and strong body, both forms of training should be used; although they both have their dangers when performed intensely, both methods can be used alongside one another. If you are a complete beginner, consider hiring a personal trainer in Crawley that will help you to avoid possible injuries and get maximum results.

The key to unlocking your desired results comes from correctly following these training methods, and supplementing them with a diet that is tailored to your fitness goals.


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This post contains affiliate links, so we may earn a small commission when you make a purchase through links on our site at no additional cost to you. Read our disclaimer

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