Swimrun races with high swim/run ratio, taking place in big open water, put high demand on the swimrunners ability to navigate. If the race is known to demonstrate changeable wind, current and wave conditions, this skill becomes even more important.
If you do a coastal type race, it’s easy enough to navigate even though this most likely mean having to breathe on the coastal side during the swim. However, when swimming point-to-point races and over large open sea, there is the chance to deviate from the planned course without knowing it. Especially if the winds and currents are strong. This is the reality for many races, as we could see during this years Hvar swimrun race and also a challenge for the ÖtillÖ main race.
What most racers usually tend to miss in island swimrun races is that the current, despite the wind direction, tends to change and re-shape when passing an island or narrow gap. Usually also picking up in strength in certain areas.
Then how does one swim across a swimrun stage like this?
If the water and wind are calm and you’re a strong swimmer with good navigational skills, then it’s advisable to go directly across (green, picture below). If you however have difficulties swimming in a straight line, or tend to navigate poorly, any wind and current will push you away, leaving you to make up for lost ground towards the end of the swim (red). This mean having to swim head-on against the current, losing a lot of much needed energy for the upcoming run.
Ideally, in bad weather circumstances you already want to make space in the beginning to be able to ‘rest’ later on during the swim. By taking the fight directly (yellow), being fresh and rested in your shoulders, you put yourself in a position where you towards the end of the swim can use the current to your advantage and drift to the exit point. Saving energy for the coming run stage.
At the ÖtillÖ main race, the challenge of reading and navigating the water becomes obvious for many swimrunners when they hit the ‘pig swim’ stage. Here many teams end up spending unnecessary energy in the end, fighting the elements to get back on track while also losing precious time.
With a steady wind and current coming from the west (black, picture below), the swimrunners are left with 3 choices; 1. Go in a straight line (green) meaning having to navigate at a high frequency to stay clear of any drifting, disrupting the flow of swimming and loosing time. 2. Go with the current (red) and make up for lost ground towards the end (lower navigation frequency, high energy loss), or 3. Fight the current straight on (yellow), and then drift down towards the exit point (high energy output early on, low navigation frequency). The picture below illustrates the reality for the majority of teams and where they end up swimming.
Pay attention to how most of the safety boats end up positioning themselves to safeguard the swimmers.
The 1400 meter ‘Pigswim’ at the ÖtillÖ swimrun race, 2016.
Despite the majority of teams having this crucial information when approaching the water, they still end up swimming the long high energy consuming detour (red).
So all-in-all. If you take a moment to read and analyse the situation before hitting the water, you will save precious time and energy towards the end of the swim.
A few check-points to have in mind for a race:
1. Will you have strong wind?
If so, you probably want to re-think your strategy of swimming head on in a straight line. For each swim, read the water and wind direction and plan your swim before entering the water.
2. Is the wind direction going to be constant?
If the wind will be constant during the day, you should plan your entry points and swim direction and then stick to them, regardless of what the team in front of you does.
3. Has the wind changed direction during the last couple of days?
If so, expect ‘choppy’ water. In these conditions it can be difficult to read the currents and the swims will usually be messy. It will most likely be hard to navigate under these conditions
4. Are any swims open and exposed to the ocean?
Then expect big waves and strong current in narrow passages.
5. Will you swim among islands?
Expect strong currents in narrow passages. Pay attention to the currents that bend themselves around the tip of the island. If you end up in these currents, you might have to swim with the wind but against a very strong current.
Strong wind and currents usually mean much colder water conditions, especially in the narrow sections, so pay attention to the expected water temperature.
And lastly, never ever use a safety boat for navigational purposes. They move constantly. Always find a fixed point to lock on-to, agree with your partner and co-navigator, and start to swim.
/The WoS Team