blood glucose levels

Posted 2 years ago

Tracking blood glucose levels

You may have seen bodybuilders on Instagram posting up stories from their glucometer, showing their fasted or post prandial (90 minutes after eating a meal) glucose levels. You might find this odd because you tend to only see diabetics track these values; however, it is becoming increasingly common to do so amongst bodybuilders, as there is a lot of value in having this data.

In spite of its growing popularity, as with many things, those who start tracking their glucose levels don’t really know why they’re doing it, and/or do not know how to interpret the data from the readings. Therefore, in this article I will explain how glucose is disposed of in the blood, to give you some context to understand what those readings might mean, and I’ll discuss why we would track it as bodybuilders.

How do we process carbohydrates?

Before we get into explaining why tracking blood glucose levels is important, we must first understand how the body processes carbohydrates. Carbs can be simple (rapidly digested) or complex (slowly digested), but all carbs are broken down into simple sugars – in the form of glucose – that can be easily transported throughout the body and be delivered to vital organs and working muscle groups.

Our body can obtain glucose from a variety of sources: we can get it from eating (food broken down into glucose), but it is also stored within the body in the form of glycogen, in both muscle tissue and in the liver. Our body also stores excess glucose in adipose tissue, i.e., our body fat. The last and final way we could obtain glucose is through a process called gluconeogenesis, which involves the breaking down of protein (muscle tissue) to obtain energy and will occur in times of starvation.

After we have ingested a meal, our blood sugars will begin to rise. This is not a bad thing – in fact, it’s needed, especially if we are going to be exercising, as it means glucose (which is energy to our body) is readily available in the system. Importantly, this rise in blood sugar triggers the pancreas to realise insulin. Insulin is a hormone that travels around the body and tells all cells (not just muscle cells! Insulin communicates with all cells, which is why glucose can be stored in fat cells) to open up and let that glucose in, a process that ultimately lowers our blood sugar levels back to baseline, prior to eating our next meal.

Without insulin, our body can’t use or store glucose for energy, and the glucose simply remains in the blood unused. In type 1 diabetes, the body doesn’t produce insulin, which is why type 1 diabetics must inject their own insulin throughout the day to process the (glucose from the) food that they eat. Type 2 is different, as in this case, the body is able to produce insulin but its cells have become “insensitive” to insulin’s message, due to chronically elevated blood sugar levels, which is linked to obesity.

If blood sugars remain chronically elevated (hyperglycaemia) for extended periods of time, it can lead to: cardiovascular disease, vision problems (potential blindness), nerve damage, circulation problems in feet (leading to amputation), bone and joint problems and also teeth/gum problems.

Blood glucose levels

It is important that we know that the ranges for “normal” blood glucose levels vary between individuals with or without health conditions that might affect these factors (such as type 1 and type 2 diabetics). The table below indicates what the recommended target blood glucose ranges are for different population groups, and these measurements are taken by using a glucometer (taken from [1] These figures would be deemed as perfect ranges, when in reality readings might be different from individual to individual.

Fasted blood glucose levels here are taken upon wake, usually after the consumption of some fluid, and having eaten the night before. What that reading is telling us is how much glucose is circulating within our blood, and if we are non-diabetic, how well our body – specifically, insulin – is doing its job of helping us shuttle glucose into cells.

However, we can’t just assume that if we get one high reading that it means our body isn’t in an optimal place, as there are a number of different factors which can affect those readings. Some of these include: eating later than normal the night before, high stress levels, dehydration, poor sleep quality, and poor digestion, just to name a few.

It therefore makes sense to track these fasted blood glucose readings for a given period of time, such as a few weeks, before drawing a definitive conclusion about our body’s functionality. When doing so, I also recommend that you check your bloods post prandial. This data, paired with your fasted readings, should give you an indication as to how well your body is handling the food you are putting in it, and how much insulin the pancreas can produce to cope with those demands.

Why does it matter?

As a male bodybuilder it’s no secret you have to eat large amounts of food in your gaining phase to add muscle mass. This of course comes with adding a fair amount of overall weight (30-40lbs) and alongside it, some body fat. What we want to try and do is keep our body in the most optimal position for growth as we push our bodyweight up. By doing so, it’ll mean that we minimise the rate of fat gain and we maximise the rate of muscle gain. In essence, this allows us to bulk for longer and to have less body fat overall by the time we get to the end of a push phase. As such, we can use these readings as guides and contributing factors to decision making processes in a gaining phase.

In simple terms, if readings are siting towards the bottom end of the range, it suggests that your body (insulin) is efficient at telling cells to open up and allow glucose in; however, if we’re sitting at the lower end, it will more readily be telling muscle cells to do this over fat cells. If readings are towards the top end of the range, then what it is telling us is that our body (insulin) is inefficient at telling our cells to open up and let in that glucose, and that it will be more readily telling fat cells to do this over muscle cells. Therefore, you can see that if you are walking around with higher levels of blood glucose, then this isn’t an ideal scenario for trying to build muscle mass and instead, you’ll be promoting fat gain.

Assuming you’ve been tracking your pre/post prandial blood sugar levels from the start of your bulk, what could it mean if you are halfway into you gaining phase and you start to see higher blood glucose level readings? For example, imagine that in a fasted state, you are continually seeing 6+ mmol/L and post prandial, 8+mmol/L. It could either mean that 1) you are eating too much food and need to adjust your intake to get these within range or 2) your body fat levels are too high, and you must now diet to become more insulin sensitive. If you were to continue to mass in either scenario then it would simply lead to the accumulation of body fat at a high rate. Therefore, knowing those figures and being able to interpret them and act accordingly will ensure your physique is always at its best and most optimal for your gaining phase.

It’s worthwhile noting that there are some conditions in females which will promote higher blood glucose level readings, namely PCOS and endometriosis. If you speak to your local GP, elevated blood sugar levels can be managed with medications such as metformin.

Metformin is actually the medication that is given to type 2 diabetics to help them control their blood sugar levels and improve insulin sensitivity. You may also see some bodybuilders use long acting (lantis) insulin or short acting (nova rapid) insulin to help control their blood sugars. This is often due to the large amounts of food that they have to eat whilst trying to add large amounts of muscle mass and stay relatively lean whilst doing so. Although it seems like a dangerous practice from the outside, it can work very well if and when managed correctly.

In summary, our body shuttles blood glucose into muscle and fat cells through the hormone insulin. We can check how insulin sensitive we are by using a glucometer, tracking its readings at 90 minutes prior and post eating. In non-diabetics, this can tell us how efficient our body is at handling the food we are putting in, as well as indicating whether we need to reduce it, diet down, put more food in, or perhaps need to intervene (such as metformin/insulin) to bring those readings down. This can be invaluable when trying to add large amounts of muscle mass but also beneficial for women with PCOS and endometriosis who wish to body build.

Vaughan Wilson Bsc Hons