A few more details:
Try to keep the foil as close to the water’s surface as possible.
The less water the foil has on top of it, the less friction it has to exert on the water. You’ll immediately notice how much lighter it is when the foil is high and how everything seems to be harder when the foil is low. But it’s very easy to say “keep it high” and not so much to keep it high all the time; that’s what the other tips are for.
Plug in a straight line
If we’re turning, we’ll lose focus on efficient pumping. We’ll have to accelerate our pumping to gain speed before the turn. We’ll lose some balance in the turn and waste energy correcting it.
If you want to optimize your pumping, the best thing to do is to pull straight (or almost straight) lines. Find a place where you can walk as far as you can, like a creek or a lake with a path along the shore. If you have to swim back, you’ll lose the desire to go far and you’ll tire quickly. This will also give you visual motivation during the ride, as you see yourself surpassing places you previously stopped.
Also, if you pump in circles, your mind will be tempted to give up every time you pass near the dock, and you’ll practice less, push less, and find your true physical limit more difficult.
The Wind Has a Big Impact
A light breeze that can’t really be called wind will greatly influence your pumping. You’ll feel light and agile going downstream, but as soon as you turn around, it will seem like nothing is working anymore, as if the water were exerting more resistance.
The Current
Although it may seem unbelievable, if you take a river with a gentle countercurrent, you’ll go much better than going downstream. On the same day in the same spot, I’ve noticed that I move twice as far upstream as I do downstream.
I think this may be due to the previous point: for the foil to travel at the same relative speed with the current in the water, you have to travel at a much higher actual speed out of the water, so the external air resistance is much greater.
Water Temperature
The colder the water, the denser it becomes and therefore exerts more resistance on the foil, so you’ll always do a little better in the summer. But that’s no excuse to stop pumping in the winter; the difference isn’t that big either.
Change Spots
Despite theoretical advice, you’ll need time and practice to progress, and therefore, you’ll need motivation. One way to find motivation is to change spots. By changing, you’ll find new challenges, places to aim for, places to launch from, different wind and current conditions…
Change to a Smaller Stab
I already mentioned this at the beginning, but it’s worth remembering: a smaller stab will give you more lift, although you may lose some balance at first; it’s a matter of practice.