What is insulin sensitivity?

Posted by Ben Simpkins on April 4, 2017

A lot of our personal training clients have heard the word insulin branded about here and there but not many of them truly understand the process that it is included in so we thought we would explain it a little bit for you so you can try to control it a little more an aid you on your weight loss and toning journey. Your body’s insulin response will vary depending upon many variables like your genetics, your exercise routine, your dietary intake and your weight.

Not only can it lead to a healthier life, but getting your Insulin Sensitivity, IS, in place means that you could lose body fat quicker and also improve your athletic performance, so it is definitely something that is well worth taking the time to figure out and understand.

By now hopefully you know it is not just as simple as calories in vs calories out otherwise a lot more people would be in much better shape. You need a full body approach, you have to be eating right, drinking enough, training smarter and have your body firing on all cylinders.  So let’s look at insulin and why it can be your best friend or your worst enemy.

What is insulin?

It is a hormone that is secreted by your pancreas when you eat and is activated when you eat either carbs or protein. When you eat either of these two food sources your blood sugar will raise once the foods have been digested so to get the sugar out of your blood system the body releases insulin which opens up the muscles and cells to allow your body to replenish your glycogen stores within the muscles that get used up throughout the day and once you have fully replenished your system then your body will store the excess sugar as body fat in the cells to keep it for a later date.

What is so important about it?

Insulin will either aid your body in building muscle by improving your amino acid uptake in the muscles which improves how quickly you will rebuild your muscle or it can ensure you store as much body fat as possible.

The other issue regarding insulin is if you become insulin resistant then that is when you become diabetic. This is type 2 where the body cannot create insulin to deal with the excess sugars in your blood system so it is pivotal in not only getting results but also in overall health.

Your insulin sensitivity will also change as your bodies changes, and this is why people hit plateaus in their training programmes, you cannot eat the same and constantly lose weight. As your weight and body fat drops, your insulin sensitivity is increased. Your IS will also increase the more weight training you do too, and will remain at a heightened state for up to 45 minutes after your training session.

What should you do about it?

First and foremost, get your body fat levels down! Try to get your body weight down to a healthy level as this will have a significant impact on your IS. After this the next step would be to look at resetting your IS by trying to eliminate them as much as possible from your diet and then slowly adding them back in to find the best level for you so that you are using the carbohydrates and not storing excess fat.

Are there any issues? 

The trouble with any calorie or carbohydrate deficit is that your body will require nutrients from elsewhere, it will look to take nutrients from anywhere possible often leaving you feeling depleted, tired and can lead to some illnesses. You must ensure that you are eating nutrient dense foods like fruits and vegetables for your carbohydrate intake rather than pasta and rice.

If you are either in a nutrient or calorie deficit for too long your body will start to become stressed and this can lead to a whole other list of issues so ensure that you are eating enough calories but of the right types of food.


First and foremost, cut out unnecessary carbs and focus on getting your weight down. These will have the single biggest impact on improving your IS in the next few months, once that is down then you can look at ways to improve it and how to use it to assist your training and lifestyle.

We will create a list of tips for you to follow next week to ensure you have guidelines to follow but as we have said, make sure you focus on losing your body fat and cutting out the bad carbs.

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