A Pre-Workout Built for Performance. and Your Health.

Take control of every session with Stim-Pre-Pump — fully dosed, transparent, and engineered to perform without wrecking your long-term health.

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One Product. One Formula. Zero Filler.

Rein Nutrition makes one thing, and we make it right. Stim-Pre-Pump is a high-stim, fully dosed pre-workout for athletes who want explosive pumps, locked-in focus, and real endurance — without proprietary blends or a brutal crash.

Buy Now — $59.99

Dosed With Purpose

Three hero ingredients only — at a glance. The full breakdown lives on the Ingredients page so you're not repeating the whole label here.

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Black circular sign with white text and graphics. Centered large number 10 with a small G to the upper right of it, and the word 'Speed' at the top.

L-CITULLINE

2–3x the typical pre-workout dose for bigger pumps and better blood flow.

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BETA-ALANINE

More reps, less fatigue — clinically backed dosing that keeps you going.

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CAFFEINE

+ L-Tyrosine Laser focus and tunnel vision, no jitters, no crash.

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Health Shouldn't Be the Price of Performance

Most pre-workouts are built on hype and cheap, under-dosed fillers. Rein was built on the opposite belief — that what you take to perform should also support your health, recovery, and the long game. We don't cut corners and we don't chase trends.

Our Story

Built for the Way You Train

  • Vasodilation that actually shows up by your second set.

  • Clean, tunnel-vision energy that lasts the whole session.

  • Push more volume without gassing out early.

  • Layered energy that lets you down easy instead of dropping you.

What Athletes Are Saying

5 stars by 100+ customers

"The best pre-workout I’ve ever used! Would recommend to anyone"

— Glen Keating

"Awesome taste, great pump and perfect stim balance! Plus you can’t beat the amount you get for the price! Highly recommend"

— ScarbroughKM

“It actually gets me going, gets my focus and attention stimulated & make my workouts more productive”

— Richard DeBerry

Rein was founded by coach Chase Gloeckner, who got tired of choosing between products that worked and products that were safe to take every day. Stim-Pre-Pump is the standard he wanted and couldn't find.

Made by Someone Who Actually Trains

Meet Chase

Common Questions

  • 220mg — strong but not reckless, balanced with theobromine and tyrosine for a smooth ride.

  • Yes. It's formulated for daily training, not just occasional use.

  • Mixed Berry, mixes clean with no grit.

See All FAqs

Take Control of Your Next Session

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