Research theme
A plain-language synthesis of the Loughborough/ECB power-hitting research programme, built around a deterministic model: how far a ball travels is set by its launch angle and launch speed; launch angle is set by bat angle at impact; launch speed is set by impact location on the bat and bat speed. The article then walks back up that chain to the body mechanics that generate bat speed, and finishes with two applied questions coaches actually face — do men’s findings transfer to women, and does practising against a bowling machine change your technique.
Underlying studies: 20 male batters (club → senior international) hitting for maximum distance against a bowling machine, 3D motion capture (Peploe et al. 2018a, 2018b, 2019); 15 male + 15 female batters (university academy → senior international) (McErlain-Naylor et al. 2021); 14 male batters playing pull shots against three delivery methods (McErlain-Naylor et al. 2020).
What they measured
- Where on the bat face the ball hit (impact location, from a validated curve-fitting method)
- How fast the bat was moving (maximum bat speed)
- Bat angle at the moment of contact
- Ball speed and direction off the bat, and how much the bat twisted in the hands (bat torsion)
- Twist between hips and shoulders at the top of the backswing (pelvis–thorax separation, transverse plane)
- Straightening of the front arm through the swing (lead elbow extension during downswing)
- Wrist “uncocking” (wrist abduction/adduction during downswing)
Findings
- Launch angle is almost entirely bat angle at impact — R² = 0.83. Nothing else meaningfully competes.
- Ball speed off the bat is impact location first, bat speed second. Impact location alone explained 48% of the variance in ball speed; adding bat speed took the pair to 68%.
- The sweet spot sits 17.5 cm from the toe of the bat, on the midline. Impacts anywhere away from it lose ball speed.
- Quantified margin for error: a ball struck within 2 cm of the sweet spot across the bat face and within 4.5 cm up/down the face loses less than 6% ball speed and deviates less than 10° in direction. That is the size of the target.
- Off-centre impacts twist the bat, and the ball follows the twist. Cubic relationship between medio-lateral offset and bat twist (R² = 0.89); bat twist then predicts ball direction deviation (R² = 0.73) — the ball goes away from where the bat face was pointing. Interestingly, right at the edge of the bat the glancing contact produces slightly less twist than a bit further in.
- Three body variables explain 78% of the between-player variation in maximum bat speed, in this order of importance:
- Pelvis–thorax separation in the transverse plane at the top of the backswing — 28% (the single largest contributor)
- Lead elbow extension during the downswing
- Wrist abduction/adduction (“uncocking”) during the downswing Faster bat speeds came with more separation, more elbow extension, and more wrist uncocking. The ordering — central/proximal rotations mattering most — points to a proximal-to-distal energy transfer.
- Explicit warning against chasing bat speed: “players should not do so at the expense of accurate impact locations (i.e. timing).” Given finding 2, timing beats effort.
- Male vs female batters differ most at the lead elbow. All 15 male batters extended the lead elbow through the downswing, by 30 ± 12° on average. Of the 15 female batters, only 7 extended; the other 8 flexed the lead elbow — closer to a traditional “checked drive” than to any power-hitting technique. The authors explicitly do not know why (strength, bat moment of inertia, coaching history, or a rational adaptation to shorter boundaries favouring consistency over maximum bat speed).
- Delivery method changes the technique you are practising. Comparing bowler vs Sidearm™ vs bowling machine for pull shots: frontal-plane pelvis–thorax separation at top of backswing was greatest against a real bowler and lowest against the bowling machine; rear elbow extension was greatest against the Sidearm™; wrist backswing was greatest against the machine. Interpretation: the later the visual cues arrive, the more distally dominant (arms and wrists) the technique becomes, because timing pressure suppresses the big torso rotations.
What a coach should look for on video
Cue 1 — Impact location on the bat face
- Camera view + frame: behind-the-arm or front-on, high frame rate; scrub to the frame of contact. A chalked/taped bat face or spray on the ball makes this readable without any special equipment.
- Good: on the midline, ~17.5 cm up from the toe. Within a 2 cm-wide × 4.5 cm-tall box around that point is “as good as perfect” (<6% speed loss).
- Fault: impacts toward the edge or the toe, and — the tell without a marked bat — the bat visibly twisting in the hands at contact, plus the ball leaving in a different direction than the bat face was aimed.
- Why: impact location is the biggest single driver of ball speed (48%), bigger than bat speed.
Cue 2 — Bat angle at impact
- Camera view + frame: side-on, at contact.
- Good: the bat face angle at contact is essentially setting the launch angle; for maximum carry you want a launch a little under 45°.
- Fault: face too closed (ball driven flat into the ground) or too open (skied, high launch, no carry).
- Why: R² = 0.83. If the ball is going out at the wrong height, look at the bat angle, not at effort.
Cue 3 — Hip–shoulder separation at the top of the backswing (the highest-value bat-speed cue)
- Camera view + frame: high overhead or front-on; scrub to the top of the backswing. Transverse-plane separation is very hard to see side-on — this is the one cue where camera angle really matters.
- Good: shoulders rotated noticeably further round than the hips at the top of the backswing — hips already beginning to open while the chest is still closed.
- Fault: hips and shoulders turning as one block (“no coil”), so the player is swinging all-arms.
- Why: largest single contributor (28%) to between-player bat speed differences.
Cue 4 — Lead elbow extension through the downswing
- Camera view + frame: front-on; scrub from top of backswing through to contact.
- Good: the front arm visibly straightening through the downswing (~30° of extension in the male cohort).
- Fault: front elbow staying bent or actively collapsing/flexing into contact.
- Why: second-largest contributor to bat speed. But see the caution below for female batters.
Cue 5 — Wrist “uncock” late in the downswing
- Camera view + frame: front-on or behind-the-arm, in slow motion through the last third of the downswing.
- Good: wrists held cocked and then released late.
- Fault: wrists released early (“casting”), losing the last accelerating segment.
- Why: third contributor to bat speed; consistent with a proximal-to-distal sequence.
Cue 6 — Sequencing check (a way to read cues 3–5 together)
- Camera view + frame: front-on, full swing in slow motion.
- Good: the order is torso → front arm → wrists. Big rotations start it, small ones finish it.
- Fault: the swing starts at the hands. This is the same fault the bowling-machine finding produces.
- Why: the ranked variance contributions (28% torso > elbow > wrist) are the signature of that sequence.
Cue 7 — Delivery-method context for your video
- What to do: note on every clip whether it was filmed against a bowler, a Sidearm™, or a machine.
- Good/fault: nothing to “fix” here — but do not diagnose “no torso rotation” from bowling-machine footage, because the machine itself suppresses torso rotation. Judge separation from footage against a real bowler.
- Why: machine footage systematically underestimates pelvis–thorax separation and overestimates wrist action, so you would coach a fault that is an artefact of the feed.
Caveats and limits
- Small samples (20 male; 15 male + 15 female; 14 male), wide range of standards from club to international, and a “hit for maximum distance” range-hitting task rather than match batting.
- The bat-speed determinants (cue 3–5) come from a male-only cohort. Applying cue 4 (lead elbow extension) to female batters is explicitly not supported — see below.
- All relationships are correlational between players, not interventions. Nobody was coached to increase separation and then re-measured. “Batters with more X had more bat speed” is not the same as “increase X and you will gain bat speed” for a given individual.
- The deterministic model only really covers bat speed. The article says outright that the factors behind bat angle and impact location — arguably the two biggest ones — are still not modelled.
- Practitioner article, not peer-reviewed; but every claim is sourced to a peer-reviewed study.
Relationship to other Felton work
- The male/female comparison here is the plain-English version of McErlain-Naylor et al. (2021), catalogued in Spin Bowling & Batting.
- TENSION (sex differences): the bat-speed model says extend the lead elbow, but roughly half the female batters flexed it and the authors decline to call that a fault — it may be a rational solution to different equipment, strength and boundary constraints. So cue 4 should not be coached blind into the women’s game. This mirrors the same pattern in Felton’s bowling work, where male and female fast bowlers do not share the same speed determinants (see Fast Bowling Technique & Context).
- The closing argument — “we cannot simply coach all players in the same manner… if an ideal movement solution exists for an individual it is through an interaction with the demands of their competition, equipment, training and individual characteristics” — is the same individual-specific optimum thesis that drives Felton’s fast bowling simulation programme in Fast Bowling Simulation & Optimisation.
- The bowling-machine finding is a methodological warning that applies to any video-based technique analysis in this catalogue: the practice context changes the movement you filmed. Pairs with the grass-vs-artificial-pitch finding in Fast Bowling Technique & Context.