Ekrin B37 vs Theragun Prime

The Ekrin B37 and Theragun Prime are both serious recovery tools, which makes the spec comparison particularly relevant — the question is not just which gun performs better in absolute terms, but which fits the buyer's specific needs. The B37 wins stall force, battery life, noise level, and attachment count. The Prime wins amplitude and app integration. Weight and speed settings are tied. Understanding what those differences mean in practice is the key to making the right choice between them.

The Theragun Prime's 16mm amplitude is the specification that sets it apart from most competitors. Most massage guns — including the B37 — use 12mm amplitude, and a smaller group reaches 14mm. Only Theragun devices consistently reach 16mm due to their proprietary motor mechanism. Amplitude determines the stroke length of the attachment head per percussion cycle; a longer stroke reaches deeper into layered muscle tissue on each strike. This makes the Prime particularly effective for the glutes, hamstrings, and posterior chain, where multiple layers of dense muscle sit beneath the surface. For users whose primary application is these large, deep muscle groups, the Prime's amplitude advantage translates directly to more effective treatment depth.

At 40 lbs stall force, the Prime is well-suited to the moderate-pressure recovery sessions that most recreational athletes actually do — 10 to 15 minutes at medium speed, treating accessible muscle groups with a ball head. It excels in this use case and its 16mm amplitude makes even moderate pressure sessions more effective than what a shorter-stroke gun achieves. Where the Prime's stall force limitation shows is under heavy sustained pressure from larger users pressing into the glutes or hamstrings. The B37's 56 lbs threshold holds motor speed through that pressure range, meaning it maintains consistent percussion depth where the Prime begins to compress. For lighter users or moderate-pressure applications, this gap is academic. For heavy users or anyone who presses firmly, it becomes practical.

The 8-hour versus 2-hour battery comparison is the most lopsided specification difference between these two devices, and it is worth being direct about the practical implications. The Theragun Prime's 120-minute battery is functional but demands regular attention for daily users — at 15 minutes per session, it supports roughly 8 sessions before needing a charge, which means weekly charging at minimum. For a device used in the morning before training or in the evening before sleep, a forgotten charge creates a real interruption to routine. The B37's 8-hour battery at the same usage rate goes weeks between charges. Additionally, the B37 includes a carrying case and the Prime does not — a minor but genuine convenience difference for users who store or travel with their device.

The Therabody app is genuinely useful and not a feature checkbox. It provides curated routines organized by sport — running, cycling, strength, yoga — and by recovery goal: warm-up, post-workout soreness, pre-sleep relaxation. Bluetooth connectivity lets the app control the Prime's speed automatically during guided sessions, removing guesswork about how fast to run the gun on a given muscle group. For users building a recovery practice from scratch, this structured guidance compresses the learning curve significantly. For users who already have an established routine — experienced athletes who know which attachments to use on which muscles and for how long — the app adds little. The Ekrin B37's app-free design is appropriate for that latter group; the Prime's Therabody integration is appropriate for the former.