How to Stop Rounding Your Backhand (and Spot It on Video)

What rounding actually is

Picture your throw from above. On a clean backhand, the disc travels a fairly straight line: back along the target line in the reach-back, then forward along that same line, passing close to your chest before the arm extends toward the target. On a rounded throw, the disc swings out wide, away from your torso, and travels along an arc, like a door swinging on a hinge at your shoulder.

That arc causes two problems.

1. Power leaks out. Throwing is a chain. Classic biomechanics describes throws as proximal-to-distal: the big segments near the body's center (hips, then trunk) start the motion and the arm and hand finish it (Putnam 1993). When the arm swings wide on its own, it stops riding on that chain and starts working alone.
2. The release point wanders. On an arc, the disc's direction is changing every instant, so letting go a few milliseconds early or late sends it somewhere different. For a right-hand backhand, that usually means the disc leaves early and heads right of your line.

A useful reminder that arm effort is not the whole story: in a study of ultimate players throwing sidearm, skilled and unskilled throwers released the disc at similar speeds (21.7 vs 20.7 m/s), yet the skilled group put far more spin on it and threw much farther (51.4 vs 29.5 m) (Sasakawa and Sakurai 2008). It was a sidearm study, not a disc golf backhand study, but the lesson carries over: clean mechanics matter more than swinging harder.

How to spot rounding on your own video

You can feel rounding, but you usually cannot feel it accurately. Video settles it.

Pick the right angle

Rounding is a sideways curve, so you need a camera that looks along the target line.

• Best: directly behind you. Phone at about hip height, pointing down the target line, with your whole body and the disc in frame.
• Also good: directly in front. Same idea, mirrored. Stand the phone well off your line of fire.
• Not useful for rounding: side-on. From the side, the arm's outward swing moves toward or away from the lens, so a rounded pull and a straight pull can look almost the same. Side-on is still great for other things, like plant timing and posture.

If you need help with height, distance and slow-motion settings, see how to film your disc golf throw for form analysis.

Check these frames, in this order

Scrub through your slow-motion clip and pause on each of these moments.

1. End of the reach-back. From behind, is the disc back along your target line, or is it swung out to the side, away from your body? A reach-back that drifts wide often turns into a rounded pull.
2. Start of the forward move. Which moves first, your hips or your hand? If the hand and arm are already traveling forward while your hips and chest are still closed, the arm has started early.
3. The pocket frame. This is the key pause: the moment the disc passes your chest. On a clean pull, the disc is close to your body, the elbow is bent and leading toward the target, and the disc sits roughly in front of your chest. On a rounded pull, the disc is out past your shoulder line with the arm already fairly straight.
4. Release. Look at where your hand is when the disc leaves it. If your hand is well out to the side of your body line, the disc was on an arc.

Also check your head and upper body across all four frames. If your head drifts back away from the target during the reach-back and then lunges forward, sway is likely part of the problem.

Full disclosure: I build Disc Golf Form Analyzer. In the app, Pose Estimation tracks your body frame by frame and grades your backhand against a real coach's ideal form on 10 backhand faults, and rounding is one of them. Each fault comes with the coach's explanation, a cue, a drill and a short demo clip. The 3D Throw view is also handy here: a top-down view shows the pull path directly, and the hand trail draws the path your throwing hand took, so a curve is hard to miss.

The four common causes

Rounding is a symptom. Almost every case traces back to one of these, and many players have two at once.

1. The arm starts before the body

This is the most common one. You reach back, then the arm fires forward while your hips and shoulders are still turned away. With nothing else moving yet, the only way for the arm to go is out and around. On video, the hand moves first in the "start of forward move" frame.

2. Swaying away from the target

During the reach-back your weight and head drift backward, away from the target. To get back to the front foot you have to lurch forward, and the arm swings wide to keep up. On video, your head moves noticeably back and then forward instead of staying fairly stable.

3. A wide reach-back with no coil

The disc goes back out to the side, away from your body, instead of back along the line, and your shoulders barely turn. The pull then starts from a wide position, so it follows a wide arc. On video, the disc is off to the side in the reach-back frame and your chest still faces mostly forward.

4. The elbow drifts and the arm straightens early

The elbow stays behind or drops instead of leading toward the target, so the arm extends long before the disc reaches your chest. A straight arm swinging from the shoulder can only make an arc. On video, the arm is already straight in the pocket frame.

Weak bracing on the front leg can feed all four: if the front side does not firm up, the body keeps drifting forward instead of turning, and the arm takes over.

Drills matched to each cause

Pick the drill for the cause your video shows. Do them at low effort first. Speed comes after the shape is right.

Cause	What the video shows	Drill
Arm starts before the body	Hand moves forward while hips are still closed	Hips-first standstill
Swaying away from the target	Head drifts back, then lunges forward	Quiet-head reach-back
Wide reach-back, no coil	Disc out to the side at full reach-back	Line reach-back
Elbow drifts, arm straightens early	Straight arm at the pocket frame	Pause-at-the-pocket reps
Weak front-side brace (often combined)	Body keeps sliding forward past the plant	Plant-and-stop throws

Hips-first standstill

Stand in your throwing stance with the disc already in your reach-back. Start the forward move only with your front foot pressure and hip turn, and count "one" before the arm is allowed to move. Throw gently into a net or open field. The point is to make the late arm feel normal.

Quiet-head reach-back

Pick a spot on the ground just ahead of your front foot and keep your eyes and head steady over your stance while you reach back. If your head moves, shorten the reach-back until it stops moving. Make a set of dry reps, then a few soft throws.

Line reach-back

Put a rope, a stick or a line of discs on the ground along your target line. Reach back so the disc travels back over that line, not out to the side, and let your shoulders turn to get it there. Pull forward along the same line.

Pause-at-the-pocket reps

No disc release at first. Move from the reach-back to the pocket and freeze: disc close to your chest, elbow bent and pointing toward the target. Hold for a second, then extend the arm toward the target and finish. Once that feels natural, do the same motion without the pause and throw short shots.

Plant-and-stop throws

Throw at half power and try to finish balanced on your front leg, with your body stopping over that foot rather than stumbling past it. A firm front side gives your hips something to turn against, which helps the arm stay late.

A note on cues: research on attention suggests that focusing on the effect of a movement often works better than focusing on the body part itself (Wulf 2013). So once a drill feels comfortable, swap "keep my elbow in" for an outside cue, like "pull the disc along the rope" or "throw it through a doorway in front of me."

How long it takes to fix

I'm not going to give you a timeline, because nobody can honestly predict one. It depends on how ingrained the habit is, how often you practice and which cause you have. What you can control is how you practice.

• Keep sessions short and focused. One cause, one drill, at low power.
• Review video in batches, not after every throw. The guidance hypothesis in motor learning holds that feedback can hurt learning when it comes too often or is too easy to lean on (Anderson et al. 2005). Throw a set, then watch the set.
• Re-film from the same angle. Same camera spot, same height, so you are comparing like with like.
• Watch a good model. A meta-analysis of observational learning found that watching a model helped movement form much more than it helped outcome scores (Ashford, Bennett and Davids 2006). That fits fixing rounding: you are changing a movement shape first, and the results follow.
• Add power only when the shape holds. If rounding comes back at full effort, drop back to the speed where the pull stays straight and build up from there.

Once the pull is clean, distance work is a separate project. See how to throw farther in disc golf for that. For a broader list of common backhand errors, Innova's common throwing errors page is worth a read too.