When training, it is helpful to expose yourself to the
conditions you might encounter in the event you’re preparing for. In swimrun,
you make repeated transitions from land to water and back again. Your ideal
preparation would therefore include some time spent doing actual swimrun.
However, in the real world, that is not always practical. For example, you might not have access to anywhere that lends itself to swimrun practice. In the winter, the cold could spoil the fun, or result in hypothermia. Even in summer, time considerations might rule out actual swimrun training.
Luckily, not being able to do your ideal training shouldn’t stop you from doing effective training. One option, which partially simulates the swimrun experience, might be to run to your pool training sessions, and run home again after.
Obviously, you won’t be running directly into the pool with your shoes on. Very few pools would allow that. You will have to rinse your sweat off before you swim, and you will have to change and put your shoes back on before setting off home again. Your time taken over the transitions will therefore be longer than in a swimrun event, and your swimming won’t be hampered by shoes and the other kit you need to carry on a swimrun. Nevertheless, you should still experience – and therefore adapt to – that strange feeling of your body not quite working properly as you transition from using one set of muscles to another.
In a race, I find that I struggle at the beginning of swims, but then settle into them after 5 minutes or so. Similarly, when I jump into the pool after running there, my arms won’t fully cooperate initially. It’s the same with the post-swim transition back to running, except with my legs, obviously. I also get out of breath unusually quickly when I run immediately after swimming. Going through this in training makes the transitions easier to handle on race day.
A big plus is time efficiency. On a Saturday morning, I can run to the pool (25 minutes), do a club training session (90 minutes) and then run home again (25 minutes or more if I take a longer route). This is a solid 2.5 to 3 hours of training and then the rest of the day is free. If I separate the activities, I’d swim in the morning and run in the afternoon, and it feels like the whole day is gone.
There are disadvantages too. One of them is running with swimming kit. I’ve tried various options. The best is persuading someone else to take my kit to the pool for me but failing that I use a small rucksack and only take the bare minimum. That means no paddles or pull buoy – and if you’re going to use those for racing, it’s good to practice with them too. But even a small rucksack makes running feel different and less free, plus it makes my back sweat, so I need to carry a second t-shirt.
The second issue is the quality of the running. Running to the pool and back is fine for base miles but anything that involves a change of pace or high-intensity intervals is challenging. Carrying a bag makes quality work difficult. Running hard before a swim session will compromise your swimming (in my case, it would increase the chances of getting cramp), and doing the hard running when you're fatigued after swimming might increase your injury risk.
The optimum, therefore, might be to run to some swim sessions but not all, and to schedule in runs that don’t come immediately before or after swimming when you can do interval or tempo sessions. Doing steady base miles, in both swimming and running, will be great for your swimrun development, but it’s even better if you can also do separate high-quality swim and run sessions.