Most swimmers I watch do not have a weak backstroke pull. They have a pull that never starts. The hand goes in, the arm sweeps down and back, and the water slides past it the whole way. The arm looks busy and the body does not move.
Backstroke was the second leg of every 200 individual medley I swam, including at two Olympic Games for Brazil, so I have spent years learning to grip water while lying on my back, blind to my own hand. The catch is a separate action from the pull, and it happens before any pressure goes on the water.
Where does the backstroke catch actually start?
In the air, at the entry, before the hand is wet. Everything after a bad entry is damage control. The arm goes in narrow and on edge.
The US Masters Swimming backstroke pull guide puts it plainly: "Enter your hand in line with your shoulder, with the pinky side of your hand entering first." In line with the shoulder, not out past it and not across your centre line, and pinky first so the hand knifes in.
The arm is also still long: "When your arm enters the water, it should be straight with your fingertips pointing straight toward the wall you're swimming toward." So at entry you are reaching, not pulling, and the hand cannot push water backwards.
Why does my hand slip through the water in backstroke?
Because you start pulling from that straight, fingertips-forward position, which has almost nothing to hold.
Between entry and pull there is a reposition, a change of direction for the hand: "To get into your pull position, move your hand to point your fingertips to the side wall." Fingers to the side wall, elbow starting to bend, so palm and forearm turn to face your feet. Only then do you have a surface to push with.
And the guide says, in so many words, not to rush it: "You shouldn't start pulling until you've created that hook, so don't apply pressure on the water until you reposition your hand." That one sentence fixes more backstroke than strength work does. Set the shape first, push second. Same sequence as in the freestyle catch, and the cost of skipping it is higher in backstroke, because you cannot see it.
How much should I bend my elbow in the backstroke pull?
Enough to make a hook out of your arm. Published guidance is genuinely vague about the angle, and I will not invent a number for you.
The sources agree there is a range, and that it trades depth against bend: "You can have a very bent elbow that's a little deeper in the water or a straighter elbow that's shallower in the water." Both work. Either extreme does not, and the guide names both. Too little: "Not enough bend in your arm." Too much: "Immediately pulling by over-bending your elbow and bringing your hand alongside your body is also ineffective."
That second one is the common adult fault: the elbow collapses, the hand tucks beside the ribs, and the arm travels a short distance with no leverage.
How the bend happens matters as much as the amount. The US Masters Swimming article on swimming backstroke properly says to "Bend your elbow early, without flexing at your wrist, and keep your hand and forearm on the same propulsive plane." Bend at the elbow, keep the wrist firm. If the wrist folds, hand and forearm stop facing the same way and you lose the surface you built.
How deep should my hand go?
Deep enough to be under water that is not already moving, which is deeper than most people think, because the shoulder has to roll out of the way first.
I could not open a single source with a backstroke hand depth figure, so there is no number in this post. The pull guide commits only to the principle: "Part of that process is making sure your hand gets deep enough."
Depth comes from your body, not your arm: rotation around the long axis drops the shoulder and lets the arm get under you without reaching sideways. The backstroke article ties the catch to that: "A proper catch allows for the opposite hip to become engaged and recruit more power throughout your core." And it adds a condition: "This can only happen when you have a straight bodyline and your hips at the surface." If your hips are low, the catch is compromised before your hand moves, so fix sinking hips in backstroke first.
Which direction should I push, and where does the pull finish?
Straight back towards the wall you left, and the pull finishes at your hip.
Once the hook is set, the job is simple, and it is not a sweep. The pull guide reduces it to a line: "All you do is push straight back toward the wall you're leaving."
Hold that pressure, but know what the end of the stroke is worth. The pull guide is honest about it: "Toward the end of your pull, you're going to get less and less out of it." Finish the stroke, and do not try to squeeze speed out of the last few centimetres.
The exit comes from the shoulder, not the arm. The article describes the shoulder rolling up and "helping bring your hand out of the water thumb first", with the arm "as it makes its way to your hip and the end of your stroke". Thumb first, at the hip, carried by the roll. That sets up everything in how to swim backstroke faster.
How does SwimRead read this part of your swimming?
It does not read backstroke, and you should know that before you film a length.
The SwimRead home page states that "The current beta supports freestyle filmed from the side of the pool", and that "Backstroke, breaststroke, butterfly, underwater footage, starts, and turns are not supported analysis modes in this beta." What it does is read your freestyle: "On-device pose detection estimates up to 33 body landmarks in sampled video frames", from a clip the page specifies as "Aim for 10 seconds of continuous freestyle", filmed "in landscape from the side, with the whole body visible, a stable camera, standard lens, and normal playback speed." The output is a measurement report, not a verdict: "These estimates are not validated technique grades."
So for backstroke, you are the analyst. Phone on the deck, filming from the side, watching one thing: does the hand change shape before it starts moving backwards.
What should you drill this week?
- Pause at entry. Freeze for a beat with the arm in, straight, fingertips towards the far wall, before you reposition. Six by 25 m. It forces the two phases apart.
- Single arm backstroke. One arm, the other at your side, four by 25 m each. You feel whether the hand hooks or slips.
- Fingers to the side wall. Easy backstroke, 100 m, one cue only: fingertips to the side wall before any pressure.
- Film one length from the side. Watch the elbow. If the hand arrives beside your ribs early, you are over-bending the arm.
My free swim pace calculator turns those 25s into a pace per 100, so you can check whether a better feeling catch is actually faster.
SwimRead is free while in beta, and invitations go out as beta spots open, with paid plans coming later and beta testers told before anything changes. If you want a reading of your freestyle, join the beta and leave your email.