NHS Couch to 5K and type 1 diabetes – an experiment of N=1


Alex Silverstein
Diabetes Education Lead

On March 12th 2020, in a small 5-a-side football pitch in Camden North West London, located opposite a pub that was often frequented by Amy Winehouse, my friend Sam passed me the ball. I took it around two players and fired a shot into the left-hand side of the goal, the fans at my 5-a-side pitch went wild (all two of them) and the whistle (after 40 minutes of playing) blew for full time. This was the last time I completed any form of real aerobic exercise.

March 12th was also the last day I was in my office and, since then, I have generally tended to spend the majority of my working day sitting on my “couch” akin to Garfield the cat.

I work as the diabetes education lead for the NHS Know Diabetes Service, which involves overseeing the rollout of programmes and information to help people learn about diabetes in a way that suits them, so they can live their lives to the full.

One such programme, soon to be promoted by the Know Diabetes Service, is the NHS Couch to 5K app; and given my current predicament, I decided I would give it a go myself. It’s worth saying at this point, I also have type 1 diabetes, so consider this two-part series of blogs an experiment (of N=1) into the impact of the NHS Couch to 5K app on living with type 1 diabetes.

I have lived with diabetes since I was 18 months old and trust me, in my 30 years of living with type 1 diabetes, every day is an experiment. In fact, I don’t think Einstein had full appreciation of the challenge of experimenting with exercise and of type 1 diabetes when he said that “the definition of insanity is doing the same thing and expecting different results”.

Over the next 9 weeks of experimenting with type 1 diabetes and Couch to 5K, I am expecting a lot of different results. For that reason, it is important to also state that you should consult a healthcare professional before trying to replicate any of the experiments in this blog post.

As for the main experiment, and following the structure I learnt to run experiments as a 12-year-old during my GCSE chemistry lessons, you should start every experiment with a testable question, conduct research, state a hypothesis, design and carry out your experiment, collect data and finally draw your conclusions. In my case, the testable question is “can I run 5K using the NHS Couch to 5K app with type 1 diabetes?” 

Next is the research, the NHS Couch to 5K programme is a nine-week course that utilises a popular concept called interval training, where you move at different speeds during a running session (lasting no more than 30 min at a time). By varying your pacing, your body is forced to adapt to different speeds, your heart and lungs have to adapt to various levels of strenuous activity (and get stronger/healthier as a consequence). As a result, you actually burn more calories and get fitter, compared to just training at a constant speed.

Each run is sandwiched by a five-minute brisk walk to warm up and cool down, and a day of rest in between every run. Every week you will increase the amount of time spent running and reduce the time spent walking until you are able to run/jog for 30 minutes without walking in week nine. Dependent on your fitness level it may take longer to get to that level, but the aim of couch to 5K is to be progressive in your training. The table below highlights how these changes (week by week). More info about the NHS Couch to 5K app can be found here (1).

My hypothesis is that I should be able to complete the 9-week course, assuming I avoid injury. However, running 5K in 30 minutes is actually quite fast, so I am not entirely confident I will reach that goal. 

From the information I read and the YouTube videos of people trying the app, this programme is not about weight loss and I don’t expect to lose any weight. If you are overweight and have diabetes, please read our tips for staying safe whilst exercising here. If you want to lose weight, then you will need a different blog/experiment, most likely involving a change of diet (in addition to exercise). You can check out some of our other programmes for weight loss here.

The design of the experiment is to use the NHS Couch to 5K app and follow the course, as dictated by one of the four coaches you get to choose when you download the app (image below). The app also comes in a podcast, which you can play over your running playlist. I went for Michael Johnson as my coach, because I always enjoyed his commentary on the BBC Olympics coverage and well, he is an ex-professional runner.

As I have type 1 diabetes, treated with an insulin pump and a continuous glucose monitor, I will also have to ensure that my blood glucose is at a safe level before going for a run (for me this is no less than 5mmol/L), as well as deciding what to do with my insulin pump, which is a device the size of a pager or small mobile phone, connected to me via a thin plastic cannula.

If you take injections to manage your diabetes (e.g a basal/bolus regime) then again you may wish to understand how to manage your carbohydrates and insulin intake before, during and after running with your healthcare team. Before speaking to your healthcare team, you may wish to visit websites like Runsweet (3) or Excarb (4) for advice or consult a peer group (5). It is common with aerobic exercise like running/walking that sugar levels may drop afterwards, especially when you complete longer distances. Therefore, you should plan with your healthcare team how best to manage this (either before, during or after your run).

Finally, looking after your feet when you have diabetes is incredibly important and therefore, I needed to make sure I have adequate and well-fitting running shoes before I began. Again, before you start your own experiment with diabetes and couch to 5K, do consult your healthcare team for individual advice that is catered to your own needs (and any previous sports injuries).

I have some old football injuries, so I found the 5 min brisk walk (to warm up and an additional 5 min brisk walk to cool down) to be insufficient. Therefore, I used a YouTube video to help me (2).

My Experiment

Now let’s start with the experiment and the data collection. To help me, I will use the data from my continuous glucose meter, which is a sensor that measures my sugar level every 5 minutes and displays it via an app on my phone. That way I can track how my sugar level changes both before and after my run. I also found an app for measuring the distance and speed of my runs to see if I actually go 5K.

Week one of couch to 5K involves three runs of seven repetitions of 60 seconds of running and 90 seconds of walking, you then do one final run of 60 seconds before finishing with another five-minute brisk walk to cool down (image above for how it looks in the app).

Michael Johnson was in my ear throughout telling me when to change between walking and running, as well as a little bell to notify me when I was halfway through the run. With regards to the running, it wasn’t too challenging, but I do now appreciate the research I mentioned above about interval training.

Furthermore, seven rounds of stopping and starting made it more challenging than if I had just tried to run 3.5km without stopping. My pace was also 6.20 minutes per km (needs to be 6 minutes per km if I am to run 5K in 30 minutes after 9 weeks of training). After the running part, I completed my 5 minutes of brisk walking to cool down and Michael Johnson said I should have some water and a banana to replenish my hydration and energy stores.

As for my diabetes, this is where the first experiment really began.

Before the run, I decided not to wear my insulin pump; similar to when I play football (although this is due to the rough nature of my 5-a-side opponents). I didn’t want it bouncing around in my pocket whilst I ran, as it would be quite distracting.

I started with a  level of 6mmol/L, which is in my target range (of 4-8.5mmol/L), and then two hours after my run, my sugars started to spike to 13.3mmol/L, before steadying off at 7.6mmol/L after I took some insulin to bring it down. Now, this may be due to three reasons:

  1. The fact I wasn’t wearing my pump for 45 minutes (combined time of run + shower) meant that I wasn’t receiving any of my fast acting (Novo-rapid) insulin. As you can see from the graph below, the impact of Novorapid peaks after two hours and this may have therefore caused the spike 2 hours after my run.
  2. It could have also been the fact that I had a banana without taking any insulin to counterbalance. Considering the run wasn’t incredibly strenuous, this may have sent my sugars high.
  3. Due to something known as the “Dawn phenomenon”, which is where your body releases hormones that increase your sugar level when you wake up in the morning. For people with diabetes, unfortunately, your body doesn’t produce the insulin naturally to match this rise in sugar levels, so you get a spike.   

After two more runs in week one, I worked out what the issue was and managed to fix it. However, you will have to wait until part 2 of my blog to find the solution. Also, in the second part of this blog post, you will see how I got on with the rest of my 8 weeks of running, as well as my conclusions for the experiment.

Until then, and if you were at all inspired to get off your own couch, why don’t you download the app or read more experiences from people with diabetes doing NHS Couch to 5K using the links below, such as the Sporty Type 1s Facebook group or the Parkrun for people living with diabetes (6).

Download the app

References or links
  1. NHS Couch to 5K website - https://www.nhs.uk/live-well/exercise/couch-to-5k-week-by-week/
  2. Warm up and cool down for couch to 5K - https://youtu.be/i6h9HbbdLhA
  3. Website for people with type 1 diabetes who want to try exercise - http://www.runsweet.com/
  4. Websites to calculate your carbohydrate and insulin needs – https://excarbs.sansum.org/exercise-intensity-calculator/
  5. Sporty Type 1s Facebook group - https://www.facebook.com/groups/SportyT1
  6. Parkrun for people living with diabetes- https://www.facebook.com/groups/parkrun.for.people.living.with.diabetes/?ref=share



Alex Silverstein

Diabetes Education Lead

Alex is an international patient advocate, NHS employee and self-employed consultant. He currently works as part of the NHS diabetes transformation programme across North West London. His role is to help people living with diabetes (and healthcare professionals) get access to information about diabetes in a way that suits them.