// Field Evidence

Every number
has a paper
behind it.

Athlete-load monitoring isn't new. College and pro programs have used it for over a decade. What's new is who gets it. Slingshot brings the same measurement to the trainers and academies the $800 systems were never built to serve. Below is the independent, peer-reviewed research each Slingshot number is built on. Read it yourself.

We didn't invent any of this. We read it, built on it, and made it affordable for the programs it never reached. Each study below ties to a specific number a coach sees on a Slingshot report, and the line at the bottom is honest about which numbers are proven and which we're still validating on our own boards.

International Journal of Sports Physiology & Performance Backs: Session Load Score

The load number, tested for reliability in team sport

Researchers ran triaxial accelerometers on a calibration rig and then through live Australian-football matches. The combined acceleration across all three axes, the signal the field calls Player Load, stayed consistent within a single device and between devices, and still picked up real differences in how hard athletes worked.

Why it matters

Session Load Score is built on this signal: three axes of accelerometer data collapsed into one movement-load number. This is the study that shows that number holds steady enough to put Tuesday's session next to Thursday's and trust the comparison.

Boyd, Ball & Aughey, 2011 Read the study →
Journal of Sports Science & Medicine Backs: Session Load Score

Accelerometer load tracks real demand in basketball

Twelve Spanish first-division players were tracked across 16 sessions. A triaxial accelerometer separated the demand of different drills cleanly: full-court 3v3 and 5v5 carried the most load, and smaller guard-type players piled up more acceleration load than bigger players running the same drill.

Why it matters

This is our sport and our gym. Indoor basketball, real practice, no GPS. It shows an accelerometer can tell a walkthrough apart from a live scrimmage, the exact job Session Load Score has on the floor.

Schelling & Torres, 2016 Read the study →
Scand. Journal of Medicine & Science in Sports Backs: Jump Count

Counting jumps you can trust across a full session

A wearable accelerometer was checked against video through entire training sessions and matches in elite volleyball. It identified real jumps with roughly 95 percent sensitivity and precision, counting jump load as it happened on court instead of in one isolated lab rep.

Why it matters

Jump count is one of Slingshot's headline numbers. This shows a small accelerometer can count jumps reliably across a whole session, the way a coach needs it, in a real gym.

Skazalski, Whiteley, Hansen & Bahr, 2018 Read the study →
// Context: movement and effort are two different things
Journal of Strength & Conditioning Research Backs: Intensity Zones

The monitoring framework elite basketball already runs on

A review of how top basketball programs monitor players. It separates external demand, the movement and accelerometer load, from internal response, the heart rate and perceived effort, and reads the relationship between the two to judge whether a player is ready to compete.

Why it matters

Slingshot packs that same external-and-internal framework into something a trainer with fifteen kids and no sports scientist can read in five seconds. Our heart-rate signal is directional, a training cue, never a medical reading.

Fox, Scanlan & Stanton, 2017 Read the study →
Scientific Reports (Nature) Backs: HR Context

Why one number is never the whole picture

Sixteen players in Spain's top league were tracked across 19 sessions using planned load, heart rate, inertial devices, and perceived-effort scales side by side. Internal effort and external movement turned out to measure different, complementary parts of the same session.

Why it matters

It's why Slingshot reads movement load and intensity context together. Either one on its own tells a coach half the story.

Scientific Reports, 2025 Read the study →
// The gap

The research itself shows youth got skipped

A systematic review sorted basketball training- and game-load studies by level. Twenty covered elite players, nine sub-elite, and only six covered youth. The monitoring evidence concentrates at the professional end of the sport, in the same place the tools that generate it do.

This is the gap, written into the literature, not just our pitch. The players with the least data are the developing ones. That is exactly who Slingshot is built for.

Systematic review, PLOS ONE, 2020 Read the study →

Every study here is independent and peer-reviewed. The plain-language summaries are ours, written for a coach rather than a journal, and each links to the original paper. Some links land on abstract or repository pages where full text needs institutional access.

// What a coach does with it

Proven numbers only matter if they change what happens on the floor. Here's what the report puts in a trainer's hands.

01

Catch who's redlined before you add load

When a player's load climbs past his own baseline a few sessions running, it's on the report instead of a hunch. You decide who gets the hard block and who gets a lighter day.

02

Hand parents the update without writing it

The weekly report is the progress note you'd otherwise type at 9pm, or skip when the day ran fifteen kids long. Same data, none of the admin.

03

Push the right player, rest the cooked one

Intensity zones show who lived at max all session and who coasted, so the hard reps go to the players who still have something left.

Everything above is established science.  Below is what we're still earning.
// What we're still proving

We won't blur the line. A few of Slingshot's numbers are still being validated, on our own hardware, on real courts, this summer. Here's where each one stands.

Heart rate on the upper arm

Directional · in testing

We read it as an intensity cue, not a clinical measurement. How cleanly it holds during live play, from a sensor worn on the arm, is something we're testing now, not something we're claiming yet.

Vertical jump height

Count proven · height in testing

Counting jumps is well established, see the volleyball study above. Estimating how high a player got, from a sensor on the arm, is the harder problem. We're dialing it in before we put a number on it.

Slingshot's own court data

Boards in build · coming this summer

We have no field results yet. The boards are in build right now. The first numbers off a real session get published on this page, in plain sight, not buried in a deck.

Slingshot is built in LA by three co-founders. We read the papers above before we wrote a line of firmware, and our own court data lands on this page the week we have it.

See it on
your own floor

We're placing a small number of pilot units with SoCal trainers and academies this summer.