zumXR Extended-Release Caffeine
By Jon Klipstein, U.S. Army Combat Veteran & Founder of Die Tryin Co.
Science reviewed by Onur Oncer, BS Physiology (Phi Beta Kappa) and peer-reviewed published researcher.
THE CAFFEINE CURVE, NOT THE CAFFEINE SPIKE
zumXR® is a trademarked extended-release caffeine: regular caffeine wrapped in a coating that dissolves gradually, so part of your dose arrives later instead of all at once. That is the entire idea, and it is a good one.
Here's the truth: the problem with most pre-workouts is not the peak. It is the drop-off. A big single hit of caffeine anhydrous climbs fast and falls just as fast, and the back half of a long session pays for it.
Here is exactly how we deploy it. Real doses, printed on the label.
| Product | Fast caffeine | zumXR extended-release | Total |
|---|---|---|---|
| SEND IT 3.0 | 250 mg natural caffeine | 36 mg | ~286 mg |
| Project M777 (per scoop) | 175 mg natural caffeine | 37.5 mg | ~213 mg |
WHAT THE RESEARCH SHOWS
Caffeine itself is the most battle-tested performance ingredient there is. The 2021 ISSN Position Stand on caffeine confirms benefits across strength, sprint, and endurance work, with effective doses landing around 3 to 6 mg per kilogram of body weight taken about an hour before training.
The extended-release question has been tested directly. A double-blind crossover trial compared a time-release caffeine against regular caffeine over eight hours: the standard form ran higher in the blood during hours two through five, the time-release form was higher at hour eight, and reaction-time benefits with the time-release form persisted through hours five to eight when the regular form's early edge had passed. Different curve, longer tail. That is the mechanism doing exactly what the coating promises.
Where the evidence stops: zumXR as a specific branded material rides on that time-release category research and on caffeine's own mountain of data. We formulate on the release mechanism at a deliberate, disclosed dose, and we tell you which milligrams are which.
WHY THE SPLIT DOSE IS THE POINT
SEND IT 3.0 is built as a daily driver: 250 mg lands the way a pre-workout should, and the 36 mg of zumXR is there to soften the exit ramp on long sessions. M777 runs the same architecture at high-stim scale. Neither hides the math, because a number you cannot verify is a number you should not trust. That is the whole argument behind reading the label math on every tub you own.
FREQUENTLY ASKED QUESTIONS
What is zumXR extended-release caffeine?
Caffeine encapsulated in a coating designed to dissolve gradually, releasing its dose later than standard caffeine anhydrous. It is used alongside fast caffeine, not instead of it.
Does extended-release mean weaker?
No. Same molecule, different timing. Milligram for milligram it is still caffeine; it simply enters the bloodstream on a delay, which is why it is dosed as the smaller share of the total.
Will it keep me up at night?
Caffeine is caffeine, and a later release means a later finish. If you train in the evening, the smarter play is skipping stimulants entirely: Red Dot runs 9,000 mg of pure L-Citrulline with zero caffeine.
How much total caffeine is in SEND IT 3.0?
About 286 mg per scoop: 250 mg natural caffeine plus 36 mg of zumXR. The complete pre-workout guide covers how to place that against your body weight and tolerance.
READY TO GEAR UP?
Every dose above is printed on the label, in the form you actually receive. See every ingredient we use in the Ingredient Index, or take the 60-second quiz to match a formula to your training.
ALWAYS FORWARD.
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GEAR THAT FITS THIS POST
The products this article actually talks about. Real doses, disclosed labels, veteran owned.
