It was 5.30am and, muddled with sleep, I turned away from the alarm clock to focus my thoughts. Which hospital was I attending today and precisely what test was I having? Then I remembered: it was my third and final visit to Southampton General, where I was taking part in a clinical study on asthma.
The previous two visits had been great fun, though my long, narrow airways initially confused the medical team, who misdiagnosed me as asthmatic. But this test would be more harrowing. In order to see the inside of my lungs, Dr Tim Hinks would spray banana-flavoured anaesthetic into my nasal cavity and airways before carefully pushing a long tube and camera up my nose, down my throat and into my trachea. He would then take biopsies of my bronchial tissue and pump small amounts of liquid into my lungs to flush out cells.
Just thinking about it got my adrenaline pumping. What would I be able to see during the procedure? Would it hurt? And would my wife, a cancer research nurse, be furious when she returned to our home in Wolverhampton and learned what I had done during my "day at work"?
For me, however, it was all part of a process I started three months ago. I decided to endure - and film - as many medical tests as possible to make videos that can be shown in school science, health and careers lessons. The only limitation I have set to protect my 31-year-old body is a ban on general anaesthetics or any tests involving radioactive dyes or injections.
To date, I have travelled 4,562 miles, visited 20 different hospitals and had more than a dozen tests, ranging from skin-prick allergy tests to eye scans and a nerve conduction study.
The most uncomfortable procedures were the 35 spirometry tests to check if I was asthmatic. (I had to take a deep breath and forcefully empty my lungs for each one, for more than 45 minutes.) The most unpleasant was the banana-flavoured anaesthetic, which did not taste like bananas and was accompanied by a sedative drink that made my head spin. But there have been rewards, too. The best was the eye test, where I saw my retina in 3D and a picture of the blood vessels in it.
The testing has created a certain degree of marital friction. On one notable night, after the bronchoscopy, my wife made me sleep on the sofa because my breathing was so raspy I sounded like Darth Vader. It wasn't much fun for me either, as I struggled repeatedly to clear my throat.
My wife thinks I am mad. She sees procedures like this every day at work and would never willingly subject herself to half the things I have agreed to. She was not even impressed when I showed her the DVD of my lungs. But that DVD convinced me that I could create something for pupils to help them make more informed choices about their career paths.
The idea of becoming a human guinea pig was prompted by visiting schools with the science workshops I run as part of my organisation, Classroom Medics, which are designed to inspire pupils to study for a Stem (science, technology, engineering and maths) career and to encourage them to look after their health.
After talking to pupils and teachers about their knowledge of careers in the health service, I realised there was an opportunity to do a lot more. Usually their list was limited to nurse, doctor or surgeon. But, being an undergraduate physiologist and postgraduate toxicologist, I knew there were many more options.
I have met a number of pupils who are in the same position as I was 12 or 13 years ago. I wanted to be a doctor, but after the first two weeks of sixth form I knew I was never going to get the A grades that were required. Instead I studied human physiology, graduated with a first with honours, and became a teacher and lecturer before setting up Classroom Medics. It is rewarding to think that this project could make a positive difference to children's futures and careers.
After discussing the idea with Helen Liggett, science workforce lead for NHS North West's Healthcare Science Network, I collaborated with Holly Margerison, manager of Careers from Science at the Science Council, to create a list of healthcare scientists across the country who would agree to perform the procedures on me and allow them be filmed.
The resulting 40 free videos will be released in National Healthcare Science Week (9-18 March) on our YouTube channel, ClassroomMedicsTV.
When I tell people what I'm doing, most have a similar reaction to my wife. "Why would you do that?" they ask, incredulously. But they are intrigued in equal measure, usually adding: "Have they found anything sinister?" And when I show them a video of my vocal cords and explain that I am doing an educational project, they are fascinated. "We never had anything like that when I was at school," is a common response.
The best part of the testing has been meeting highly skilled scientists. The worst has probably been the editing process: choosing what to squeeze into a five-minute video from a film that can be two hours long is tough.
When this project is over I plan to carry on filming experiments on myself, because there are so many classroom topics with which they are linked. At some point, though, I will have to stop being a human guinea pig and find myself a real hobby.
Tom Warrender is a physiologist and toxicologist. His organisation, Classroom Medics, visits schools and offers hands-on medical and sports science workshops. Classroom Medics will be in the Body Talk zone at the Big Bang Fair at the NEC in Birmingham on 15-17 March
IN THE FORUMS
Tom Warrender is happy to play "human guinea pig", but what do you think about animal testing? Join the debate on the TES website.
Watch videos of Tom's medical tests on the TES website or follow his progress on his Android and iPhone apps.
Key stage 1: my body
Help pupils to understand how their body works with an activity pack from sarah morgan.
Key stage 2: heart journey
Untangle the respiratory system for pupils with a "Follow Me" card task shared by kaiyoga.
Key stage 3: breathing millions
Will your pupils need to phone a friend in sjtorrance's Who Wants to be a Millionaire-style revision quiz?
Key stage 4: bite-sized biology
Try derryclare's GCSE revision guide for the human body.
Key stage 5: antibodies and immunity
How would your immune system cope against Tom's tests? hajim's extensive A-level immune system guide may reveal the answer.
For all links and resources visit www.tes.co.ukresources024.