Serving British Army physiotherapist Kat Matthews first took up triathlon in 2015 and became a professional triathlete in 2019. After coming second place at her debut Ironman World Championships in May 2022, she took part in the Pho3nix Sub7 Sub8 Challenge and made history by becoming the first female ever to run a full Iron-distance triathlon (3.8K swim, 180K bike and 42.2K run) in less than eight hours, with a time of 07:31:54. Here, Kat Matthews shares her training secrets…

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Kat Matthews’s cardio & strength training advice

‘I train about 20-hours a week, but I don’t have a “Monday I do this, Tuesday I do this” approach, because I’ve never found it works for me. I swim Monday to Friday normally, so at least five times a week, if not more, doing 4-5K every session, which takes about 75-90 minutes in a pool. I cycle nearly every day, and I’ll run maybe three times a week.

‘A standard training day – which I might do three or four days in a row before having a day off – would involve a 90-minute swim in the morning, followed by a couple of hours rest, then a bike for maybe three hours with some intervals in, then another couple of hours off before a 60-minute run with some intervals. Running is my strongest discipline, so I don’t have to do that much of it to be good at it.

‘I didn’t change my training too much for the Pho3nix Sub7 Sub8 Challenge, which was all about taking away the variables that can happen in an iron-distance race and optimising everything from the course to the transitions – with the help of my incredible team to create the perfect conditions. I just made sure my training, recovery, sleep and nutrition was as optimised as possible, but in a fun, relatively happy, stress-free way.’

‘I train about 20-hours a week, but I don’t have a “Monday I do this, Tuesday I do this” approach, because I’ve never found it works for me.’

‘I do a bit of strength training. Basically, when I have less training, I’ll commit more time to it, maybe two or three 45-minute sessions a week, and they’ll be really structured. I’ll do exactly what I need and then leave because I don’t necessarily have the time to spend loads of time in the gym, even though I really enjoy it. I think heavy leg work compromises my cycling and running, but I’ve found good gains from doing strength training for a six-week block at the start of the season and then using those gains in my cycling and running.’

kat matthews

Kat Matthews on recovery and nutrition

‘I’ve learnt that I need at least eight hours sleep. If I can get more that’s great, but if I start going below that, I feel an uncertainty. Whether that’s psychological or physiological, I’m not sure, but for the training that I’m doing, I need at least eight hours in one go.

‘I think recovery comes from doing the right training load to start with, and only doing the sessions that are right for you on the day. If I sleep badly, I won’t do a really intensive run just because my schedule says so. I’ll evaluate things in the morning and maybe do a bike first, then consider doing the run later when I’ve had more rest, more food and I’m feeling more mentally stable.’

‘I think recovery comes from doing the right training load to start with, and only doing the sessions that are right for you on the day.’

‘If you’re training to 100 per cent, you need to eat to 100 per cent. For me, I focus on making sure I have enough protein during the day – nearly two grams per kilo of body weight – and that comes from making sure that I have protein for breakfast, for lunch, for a snack and at dinner. Carbohydrates are equally as important. I don’t calorie count, but I do make sure that I’m roughly aware how much I need to eat for breakfast, lunch and dinner, plus all of those calories that I’ve burnt during sessions.’

Kat Matthews’s vital kit:

‘Probably Cadbury’s Dairy Milk chocolate because it never tastes the same in America or Europe! In terms of equipment, I’m obsessed with heart rate, so I use my Wahoo Tickr Fit Heart Rate Monitor (£64.99) for every single session and race. I wear different models of Asics running shoes in training, and I can’t live without a good sports bra. There are so many women still not wearing the right sports bras and I feel like we need to keep preaching about that!’

Kat Matthews: my greatest achievement

‘I don’t think I have a greatest achievement yet. Coming second on my debut at the World Ironman champs is probably still the best performance I’ve had, but in terms of my experience in the sport, I’m most proud of my Pho3nix Sub8 performance because it was a team effort.

‘Going forwards, the event I’m most focused on in 2022 is the Ironman World Championships in Kona, Hawaii, this October. However, there is an Ironman normally held in November where the course is very fast, and if I’m feeling really healthy, I might just try and do a Sub8 on an actual Ironman course. That would be a really cool way of solidifying this project.’

This interview is courtesy of the Pho3nix Foundation, a not-for-profit organisation focused on promoting physical activity among children.

Words: Joanna Ebsworth | Photography: Mana

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