HIIT Training: Benefits

Now that we covered some of the basics around how to do different forms of HIIT training, the question often becomes why should we do HIIT training over other forms of training. 

First reason I like HIIT training is because it is very time efficient. You can get a lot of benefits for not that long of workouts. As the world keeps getting more complex and we all have more duties to cover, efficiency becomes more and more important. I also like that most of the workouts are often done on bikes. This reduces the risk of injuries when compared to activities like running which is very nice. 

On the metabolic side, HIIT can improve glucose and triglyceride regulation, increase insulin sensitivity, decrease fat mass and improve body composition and even enhance mitochondrial function. 

When you compare HIIT training to moderate intensity exercise (think going for a jog), HIIT actually has greater improvements in many categories. It is better at developing cardiorespiratory fitness, reduces systolic and diastolic blood pressure, improves HDL, reduces triglycerides, reduces fasting blood glucose, helps with oxidative stress and inflammation, and cardiac function. 

If you aren’t concerned with details, stop here, but if you wonder how it achieves these benefits, this next portion is for you. 

First off is lactate. Lactate is a by-product that is produced when the body is making energy but there isn’t enough oxygen, think during hard exercise. The body will produce piles of lactate in an effort to keep up with energy demands. Although it has had very bad PR, lactate is a very important and powerful molecule. Lactate itself can actually be used as an energy source for the brain and muscles. It also increases something called a GLUT 4 transporter in skeletal muscle that helps uptake more glucose (sugar) into the muscle. 

HIIT training also has direct effects on mitochondrial health. As we all learned in high school the mitochondria is the powerhouse of the cell and it is responsible for a large portion of our energy production. HIIT can increase mitophagy which is the process of cleaning out damaged mitochondria. HIIT also increases the process of skeletal muscle mitochondria biogenesis which is the process of increasing the number and size of mitochondria which is very helpful. It can also improve a muscle protein called PGC 1 alpha which improves muscle oxygen use, antioxidant defense, and even glucose management. 

So go out there and train hard, it's good for ya! 

Jelleyman C, Yates T, O'Donovan G, Gray LJ, King JA, Khunti K, Davies MJ. The effects of high-intensity interval training on glucose regulation and insulin resistance: a meta-analysis. Obes Rev. 2015 Nov;16(11):942-61. doi: 10.1111/obr.12317. PMID: 26481101.