Spiking Insulin Levels


Q&A With Matt Fuller

Hi Matt, I would love to know your thoughts on insulin spiking. What exactly is it? I've been advised that I need to eat something sweet after my training for the sugar rush (which will then spike my insulin levels). Apparently, this will assist with my weight loss - is that true? Thanks, Lynsey."

Hi Lynsey,
That’s a great question! There’s a ton of scientific research available regarding insulin production, so here’s a quick overview to break it down for you...


Firstly, what is insulin?

Insulin is a hormone secreted by the pancreas in response to detected increase in blood sugar. It controls glucose levels and keeps and regulates the levels of blood glucose so it remains at a constant and safe medium within our bodies.

What is an insulin spike?

Insulin spiking simply means that the insulin levels in our bodies rise and fall quickly. This is good for a quick burst of energy, but not for sustained endurance and as a negative could lead to putting too much sugar and/or excess carbohydrates into our body that could in the longer term lead to diabetes, rapid weight gain and fat storage amongst other things.

My thoughts on this subject...

After training, body builders will regularly combine simple sugars/carbohydrates to feed their muscles to aid in the repair of muscle tissue damage caused by resistance training. These sugar and carbs gives them a quick burst of energy to replace the energy (calories/sugars) lost during training.

When researching this subject, Lynsey, I found this article from Flex Nutrition extremely interesting and I hope you do too. 

“In 2007, a group working out of Maastricht University in the Netherlands examined the impact of adding carbohydrates on post-exercise muscle protein synthesis.

They had 10 healthy 20-somethings work out for one hour using a traditional resistance exercise protocol. The three post-workout treatment conditions were protein only (PRO), protein with a low carbohydrate dose (PRO + LCHO), or protein with a high carbohydrate dose (PRO
+ HCHO). A total of 12 servings were given every 30 minutes for each treatment condition to ensure a continuous and ample supply of both glucose and amino acids during the six hours of recovery.

Each subject returned seven days later to receive a different post-exercise treatment until all had been tested under each condition.Their results indicated that, given an ample amount of easily digested high-quality protein (casein hydrolysates), added carbohydrates had no effect on post-workout protein synthesis rates regardless of the amount of carbs given.

In support of these findings, another study more recently published in Medicine and Science in Sports and Exercise utilised a similar protocol (i.e., workouts followed by protein or protein + carbs) but this time they were more interested in the impact of creating a post-workout insulin spike.

Would it affect protein synthesis rates? Would it decrease protein breakdown? Would it trigger anabolic signalling pathways more effectively? You probably know where this is heading. The answer is no, it didn’t.

Spiking insulin didn’t reduce protein breakdown, and it didn’t enhance anabolic signalling pathways. The insulin spike didn’t even increase muscle blood flow! What appears to have happened was, because they used a protein source (whey) that has already been shown to maximally stimulate post-exercise protein synthesis as well as increase insulin levels, no further anabolic effect was possible even from an insulin spike. The insulin level triggered by whey alone was able to maximally inhibit protein breakdown, increase blood flow, and activate anabolic signaling pathways.”

For me, if somebody is regularly looking for a sugar rush (spike), I would seek professional advice as there may be an underlying problem as to why this occurs or is regularly needed. For example, semi-professional body builders or hardcore trainers will constantly need to eat throughout the day to fuel their bodies to feed the muscles for hypertrophy (rapid muscle growth). However, the majority of us who train will get the same benefits from having a well-balanced healthy lifestyle and eating habits.

If you would like further advice on the best nutrition for training, check out this "Best Foods For Training" article from my fellow HIF blogger (and top Australian nutritionist), Susie Burrell.

Your health and fitness is a lifestyle choice. Until next time, 

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Important: This article is general advice only. For further advice or information on this topic, please consult your health professional.
Tags: Q&A
Category: Fitness

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