From the indoor pool to the lake: what's really different in open water, the rules that matter, and how your first swim goes smoothly.
The honest answer first: yes, you can move from the pool to open water — you just need to know what actually changes. Open water simply means swimming in lakes, rivers or the sea, with no walls, no black line on the bottom, no pool edge to hold onto.
And the numbers show why respect beats carelessness here: roughly two-thirds of drowning deaths in Germany happen in lakes, ponds and rivers — hardly any in a supervised pool. That's not because open water is inherently more dangerous, but because out there nobody watches out for you unless you do it yourself.
The good news: with the right preparation, your first trip into open water is manageable. You don't need to be an extreme athlete — you need a safe body of water, company, and a bit of patience with yourself.
Train Smart. Play Hard. — in open water that means: understand the water first, then increase the distance.
In open water you're missing three things you rely on blindly in the indoor pool: the wall to push off and rest, the lane line for orientation, and clear visibility underwater. On top of that, temperature varies, and you often don't know beforehand how deep it really is.
A calm, DLRG-supervised lake is the ideal start — shallow at the shore, with lifeguards and marked zones. Rivers with visible current or unknown, unsupervised lakes are off-limits for beginners.
Tell someone where you are, or bring a companion. In the pool the lifeguard notices instantly if something's wrong — in a lake, nobody else will.
Enter slowly, let your face and neck adjust to the temperature before you swim. How you specifically acclimatize to cold water is covered in the next guide in this series.
10 to 15 minutes parallel to the shore, within sight of your companion, is plenty. Progress happens naturally once you feel safe.
For your first sessions, swim exclusively at supervised, known bathing spots. Before entering, check signage, entry and exit points, and visible current. If you feel unwell, cramp up, or lose orientation: turn onto your back immediately, float, raise an arm and wait for help instead of fighting.
Join a DLRG or club open water session instead of starting alone. You'll learn more about safe behavior in a lake in 60 minutes there than from any guide — and you have company from day one.
Natural waters carry different risks than the pool — mainly because nobody automatically watches out for you. Roughly two-thirds of all drowning deaths in Germany happen in lakes and rivers, hardly any in the pool. With a supervised spot, a companion and caution, the risk is well manageable.
Not necessarily — in warm water a regular swimsuit is enough. When a wetsuit pays off and how to choose one is covered in the next two guides of this series.
Look for DLRG-supervised lakes or official open water training groups in your region. These spots have supervision, marked zones, and usually other open water swimmers you can join.
One to two short sessions a week are plenty to start. More important than frequency is that every session feels safe and controlled — progress follows naturally after that.
Open Water: Cold Shock and How to Safely Acclimatize