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Guides

Guides

Longer pieces on the things a swing report measures. Nothing is asserted that was not read: the sources are listed at the foot of each guide.

The swing, position by position

A golfer stands at address over the ball with a driver, seen from the front with the stance and ball position visible. Golf setup: reading your address on video Ball position, stance width and side tilt all read from face-on. Down the line is the angle for posture. What to look for in each frame, and how tight the tolerance is. A golfer photographed from behind at the top of the backswing, club shaft above the shoulders and the target line running away ahead. What "on plane" at the top really means On plane at the top means the shaft pointing along your target line. Where the idea came from, and how little it actually predicts about the shot. A golfer just past the top, seen from behind along the target line, hips turning toward the target while the club is still high. What moves first in the golf transition Coaches say the lower body starts down while the club is still going back. Here is what that overlap looks like on your own video. A golfer photographed face-on at the moment an iron meets the ball, hands ahead of the clubhead and lead leg straightening. Golf impact position: what good ones share Hands ahead, flat lead wrist, open hips, weight forward. What each one does to the ball at impact, and what you can actually see on your own video. A golfer held in the finish position, weight on the lead foot, trail heel raised and chest turned toward the target. What Your Golf Finish Tells You About Your Swing Your last frame is a diagnosis. What a finish that falls backwards and a finish that collapses each say about the downswing you could not see. A golfer standing over a ball on a fairway, photographed face-on from a distance with mountains behind. Golf ball position: an inch is a degree Move the ball an inch in your stance and the attack angle shifts about a degree. What that does to the strike, and how to check it face-on. A close view of a golfer's hands and lower body at address, the club soled behind a ball on a mown tee area. The golf grip, in degrees of clubface angle A strong, neutral or weak golf grip moved twelve professionals' clubface about five degrees at impact. What the knuckles, the V's and pressure each do. A golfer bent over the ball in a navy top and cap, upper body and club visible against a blurred background. Golf posture: where your forward bend comes from A tour player bends forward about 41 degrees at address and roughly 16 of that is pelvis. Where the rest of it comes from is the whole question. A golfer swinging on a driving range in bright sun, seen from behind and to the side with the tee line and a low fence beyond. Your golf takeaway, and what it does not decide Down the line, your hands and the clubhead overlap when the hands reach the trail thigh. What that frame shows, and what it fails to predict. A golfer photographed from behind on a wide fairway, club above the shoulders against an open blue sky. Halfway back: the easiest frame to find Two different frames answer to halfway back. Which one has the level shaft, what laid off and across the line look like there, and what it settles. A golfer in a cap and patterned shirt at the top of the backswing, arms and gloved hand filling the frame. Cupped, flat or bowed: the lead wrist at the top Extension in the lead wrist at the top is meant to open the clubface degree for degree. Here is what the sensors and the labs actually recorded. A golfer playing out of a greenside bunker, sand thrown up in front of the clubhead. P1 to P10: the golf swing positions defined P1 is address, P7 is impact, P10 is the finish. Where the other seven frames sit, who named them, and what a position number does not claim. A golfer holding the finish, the driver shaft resting behind the shoulders and both hands still on the grip. Golf release: the rate the clubface turns Release is a rotation rate, not a hand action. What 94 tour swings measured, why roll and block both win, and what a phone frame can show.

What goes wrong, and why

Close-up of a driver clubface meeting the ball at impact, the face still turned slightly open to the direction the clubhead is travelling. Why you slice, and the two fixes in order A slice is your clubface open relative to your swing path at impact. Here is what that means, why the ball starts left, and why the grip changes first. A right-handed golfer photographed from behind on the target line, midway through the downswing with the club still above shoulder height. Over the top: what the move looks like on video Coming over the top is the arms starting the downswing and throwing the club outside the target line. Here is the one frame that shows it. A golfer photographed from behind on the target line partway into the downswing, hips and lower back visible against the fairway. Early extension: the hip move you can't feel Early extension is your hips moving toward the ball in the downswing. How to spot it on your video, what it does to contact, and the drills coaches use. An iron cutting a divot out of the turf just past where the ball was sitting. Why you hit it fat one swing and thin the next Fat and thin are two variables, not one: where the bottom of your swing arc sits, and how deep it swings. Both move with your chest, not your hands. A golfer in an orange shirt partway through the downswing on an open course, hands still above waist height. Casting in the golf swing, and what lag really is Casting is the lead wrist angle going early in the downswing. What that angle really is, where good players give it up, and why holding it backfires. A golfer in a red top at the top of the backswing, both arms up and the club behind the head. Chicken wing golf swing: the cause is earlier The bent, lifting lead arm past impact is a compensation, not a cause. What leaves it no room, what a motion lab measured, and why the frame is late. A golfer playing a shot from short grass toward a distant green, photographed from behind at a distance. Flipping and scooping: the loft you hand back Flipping is the lead wrist adding loft in the last hundredths of a second. What that costs in compression, and why the divot finds it first. A golfer holding the finish with a driver, upper body and club filling the frame at a tournament. The flying right elbow, and when it is a fault The flying right elbow is the trail elbow high and away from the body at the top. What Nicklaus and Furyk did next, and the frame that settles it. A close view of a wedge resting in sand beside a golf ball, the face and the neck of the club both in frame. Golf shank: telling the two causes apart A shank is the hosel, not the face. Two opposite deliveries produce it, five millimetres decide it, and two range tests say which one is yours. A golfer in a red top swinging on a course, weight and chest turning through under a cloudy sky. Hanging back: weight stuck on the trail foot Hanging back leaves pressure on the back foot at impact. What that does to the bottom of your swing arc, and why one fault gives you fat and thin. A golfer in a white skirt and cap swinging on a fairway, the club well past the shoulders. Past parallel: where the extra length comes from Going past parallel is mostly arm and wrist, not extra turn. What two studies measured when golfers shortened the backswing, and what it cost. A golfer mid-swing at a charity tournament, the fairway and trees running away behind. Pull shot, push shot: the misses that don't curve A pull starts left and stays left. A push starts right and stays right. Both mean your face and your path agreed with each other and not with the target. A golfer in an orange shirt mid-swing on a wide, dry course, the whole body in frame from the side. Reverse pivot golf swing: loading the wrong side A reverse pivot loads the lead side while the club is still going back. What force plates measured in that half of the swing, and how to see it face-on. A golfer in fatigues swinging on a dusty practice range, scattered balls on the ground ahead. Sky marks: why a driver pops straight up A sky mark is the driver arriving under the ball while still travelling down. What the scuff on the crown records, and the two cheapest fixes. A golfer on a driving range mat at the top of the backswing, photographed from behind along the target line. Swaying in the golf swing: sway versus slide Sway is lateral hip movement away from the target going back. Slide is the same movement toward it coming down. Only one is a fault. A golfer in a pale sweater at the end of the swing, hands high and body turned through toward the target. Why you hook the ball, and which hook it is A hook is the clubface shut to the swing path. Two degrees of it bends a tour drive 19 yards left, and your start line says which hook you have.

What the numbers mean

Golfers hitting balls at an outdoor driving range in 1947. Golf Swing Tempo: What the 3:1 Ratio Is, and Is Not The 3:1 golf swing tempo ratio was counted in 30 fps video frames. Accelerometers at 250 Hz found tour pros spread from 2.5:1 to 3.5:1. What is measured, what is assumed. A golfer photographed from behind at the top of the backswing, shoulders turned well past the hips, club above the trail shoulder. X-factor in the golf swing: what it's worth The X-factor is shoulder turn minus hip turn at the top. Where the 38-degree number came from, what the studies show, and why the figure is soft. A golfer photographed from the side partway through the downswing, hips already turning toward the target while the hands are still above waist height. What the kinematic sequence actually means Pelvis, thorax, arm, club: each peaks later and faster than the last. The measured numbers, why the order beats any single speed, and how it feels wrong. A golfer swinging on a coastal course, the club coming through and the sea visible beyond the fairway. Attack angle in golf: up, down, what it buys Attack angle is whether the club is travelling up or down at the ball. The tour numbers club by club, and what a degree is worth in carry. Two golfers on a practice range, one mid-swing and one watching, with bags and clubs between them. Average golf swing speed by handicap and gender TrackMan puts a scratch male amateur at 110 mph and a bogey golfer at 92. Where each published figure was collected, and why the datasets disagree. A golfer in dark clothing playing a short shot from the fringe, a golf bag standing on the grass behind. Dynamic loft: the loft the ball actually sees Dynamic loft is the loft the face delivers at the ball, not the figure on the sole. Tour players hand a 6-iron 20.2 degrees of it. A golfer in a dark sweatshirt at the top of the backswing, photographed close against a hedge. Ground reaction force in the golf swing, measured A force plate splits your push into vertical, horizontal and torque. What each reaches in the downswing, and why no camera can read them. A golf ball sitting on mown grass, photographed close and low so the dimples and the turf are both sharp. Smash factor: where the 1.50 ceiling comes from Smash factor is ball speed divided by club speed. Where the 1.50 ceiling comes from, the tour figures by club, and what a low reading points at. A golfer standing in a deep sand bunker, playing out toward a green lined with tall trees. Spin loft: the gap that sets spin and smash Spin loft is dynamic loft minus attack angle. The same gap that sets your spin rate also caps your smash factor. The numbers, driver to wedge. A golfer in a yellow shirt swinging out of a bunker, sand spraying in front of the clubhead. Club path and swing direction are different Club path is one instant at impact. Swing direction is the whole downswing arc. Hitting down splits them, and your aim pays for the gap. A junior golfer at the finish of a full swing on a manicured course, hips and chest turned to the target. Hip rotation speed: the pelvis peaks and fades Professionals peak near 415 degrees a second and are down to 289 at impact. What the pelvis is worth in clubhead speed, and what it is not. A golfer swinging on a hillside course above a bay, sea and headland in the distance. Driver launch angle and spin rate: the window The pair that carries furthest moves with your ball speed. What golfers at every speed measure, and where the published optimum came from. A golfer in a yellow shirt hitting out of a bunker, a cloud of sand thrown forward by the clubhead. Low point in the golf swing: where it sits The bottom of your swing arc is a measured distance, not a feeling. What a launch monitor means by low point, and how far it moves between swings. A golfer playing out of a bunker beside a line of tall trees, sand lifting in front of the club. Forward shaft lean at impact, in degrees Shaft lean is an angle, not a hand position. What the tour numbers actually measure, where the angle comes from, and what a face-on frame reads. A black and white photograph from 1950 of Sam Snead playing out of a sand trap, hands and wrists clear in the frame. Wrist hinge in golf: three axes, one clubface Flexion, deviation and forearm rotation are three separate movements. How far each one travels in a swing, and which two of them reach the clubface. A wide view of a golf hole with players walking the fairway and a bunker in the foreground. Head movement in the golf swing, measured Low-handicap golfers moved their heads 55 mm sideways by the top of the backswing, mid-handicappers 124 mm. What that means on your own video.

What your body allows

Two golfers putting on a green in bright sun, one standing over the ball and one watching. Hip mobility for golf: what the downswing uses The downswing spends about 85 percent of the lead hip's available internal rotation. The measured degrees, the back-pain link, and the screens. A close view of a young golfer at the top of the backswing, shoulders turned and the club behind the head. Shoulder turn in golf: the range your body has Roughly half of a 90-degree shoulder turn is pelvis. The thoracic rotation measured in tour golfers, and the two screens that find your ceiling. A golfer holding a full finish beside a course bin, back arched and weight fully on the lead foot. Lower back pain and the golf swing, measured Golf's most common injury. The compression and shear modelled in the lumbar spine during the downswing, and why the crunch factor did not predict pain. A player crouching to read a putt on the green at the Open Championship, another walking in with a caddie behind. Golf swing speed by age: what actually declines Tour driving distance falls about half a yard for every year of a player's age. What has been measured in older amateurs, and the training that moved it. Golfers hitting balls side by side at an outdoor driving range, a marquee and a line of flags behind them. Golf warm up: what it is measurably worth A dynamic warm up beat static stretching by 1.9 m/s of club head speed. What the trials measured, how long it lasted, and how few golfers do one.

Making a change stay

A golfer crouching behind a ball on the putting green, reading the line before playing. How long a golf swing change takes to stick Twenty-one days came from plastic surgery patients and 10,000 hours came from a paperback. What the retention research measures instead. Rows of range balls laid out on a dark surface, most of them white with a few coloured ones at the top. Blocked vs random practice: the retention trade Blocked reps flatter the range session. Random practice looks worse inside it and holds better afterwards. What the golf putting trials actually measured. A golfer in fatigues mid-swing on a bare practice ground, scattered balls and a distant tree line beyond. Swing thoughts: where your attention should sit Gabriele Wulf's golfers pitched better aiming at the club than at their arms. Here is how big that gap was, and why a 2024 reanalysis shrank it. Golfers practising on a putting green at a tournament, a scoreboard and stands behind them. Video feedback: how often to watch your swing Watching every swing speeds up the range session and can cost you what you keep. The feedback-frequency studies, and a rhythm for one bucket. A wide view of a quiet practice range with a single golfer hitting balls, hills in the distance. A golf range practice routine for one bucket A golf range practice routine built around one bucket: how many balls one change is worth, what rehearsals add, and where in the tray to film. A golfer playing from short rough beside a green while a caddie and spectators watch from behind. Feel vs real: the golf swing on your screen Your body reports muscle length, not shaft plane, and six repetitions can move what straight feels like. Why your swing on video looks like someone else.

Filming and measuring

A smartphone mounted on a small tripod on the grass at a driving range, framed on a golfer taking a swing in the background. How to Film Your Golf Swing on a Phone Where to stand, how high to hold the phone, how to frame the club, and why 30fps is usually enough. The setup that makes swing measurements trustworthy. A smartphone mounted on a small tripod on the grass, filming a golfer mid-swing on a driving range. What a phone can actually measure in your swing Angles inside the camera frame are countable pixels. Depth is inferred. Club and ball speed are inferences with wide ranges, not measurements. A golfer swinging in front of a large simulator screen in a darkened indoor bay. 3D motion capture accuracy versus 2D swing video Marker-based 3D and flattened 2D disagree by about 17 degrees on X-factor at the top. What each instrument measures, and where the lab reference is soft. A black and white photograph of the Australian professional Eric Cremin swinging during a tournament in Brisbane. Slow motion golf swing video: fps is only half Frame rate decides how far the clubhead moves between frames. Shutter speed decides how far it smears inside one. Your fps menu sets only the first. A wide view of a golf hole from behind the tee, players and spectators small in the frame. Camera height and parallax in golf swing video Where the camera stands decides the angles it records. What parallax costs in degrees on a swing video, and the setup that makes two clips comparable. A golfer in shorts and a cap holding the finish on a tree-lined course, spectators behind. Down the line vs face on: what each view sees A camera measures what lies flat in its picture. Which swing faults each view can resolve, which one it loses entirely, and why the answer is geometry. A golfer hitting into an indoor simulator screen, the projected fairway lit up in front of them. Drawing lines on a golf swing video Shaft plane, spine line, hip line, the box round the head. What each one is really measuring, and why two honest coaches read the same frame differently. A line of covered bays at a driving range, seen from one end with a golfer at the far stall. Radar vs camera launch monitors, and what each sees A Doppler unit watches the ball fly; a camera photographs the impact window. Which numbers on your report were measured, and which came from a model.