Shopify engineer used a 20-day sabbatical to prototype the Intensity Pad, a struck-pad power meter for sledgehammer training with live iOS telemetry.
Key Takeaways
The gap: running, cycling, and rowing have rich power instrumentation; explosive striking movements like sledgehammer swings have nothing comparable.
Core hypothesis: unmeasurable movements don’t become programmable, so adding a power metric could legitimize sledgehammer training the way watts transformed cycling.
Hardware was brutal: a connector failed under shock load, a sensor mount died mid-session, and a mechanical design choice committed on day four cost eight days before abandonment.
By week four the prototype survived real strikes, the control unit survived drops, and an iOS app pulled live data – enough to shift the idea from concept to physical artifact.
The bar he set for himself is not a gadget but a behavior change: does measurement make striking training more legible, motivating, and programmable over time?
Hacker News Comment Review
Thread is very thin with only two comments, so no meaningful technical consensus or critique has formed yet.
One commenter sees a natural competitive application (lumberjack sport rankings), suggesting a niche but real addressable market beyond gym use.
Notable Comments
@Pay08: invokes Charpy impact testing, implying industrial-grade instrumented strike measurement already exists and the engineering overlap may be worth studying.
@1970-01-01: “I could see this becoming a tiebreaker or ranking device for lumberjack competitions” – concrete use case the founder didn’t mention.
