DIY Pre-Workout Calculator
An endurance pre-workout is dietary nitrate plus citrulline for blood flow, with a moderate caffeine and L-theanine pairing for focus. A long-event oxygen-economy serving is about 2g Beetroot Pro, 8g citrulline malate, 100mg caffeine, and 200mg L-theanine, dosed across two timing windows.
Pick your goal, event, and stim level to get an exact dose-by-dose formula, a timing plan, and the cost versus a commercial tub. We call the output your Endurance Pre-Mix.
EB says
4 actives
evidence-based stack
Step 2: Your Endurance Pre-Mix
Enter your goal, event, and stim level and hit calculate. Your gram-by-gram formula and timing plan appear here.
Gear up
Ingredients athletes actually buy
Source these once and you have months of pre-workout. Always test a new stack in training, never on race day.
- Beetroot ProNitrate-standardized for a real oxygen-economy effect, not just color. The one ingredient we do not DIY.Shop Beetroot Pro →
- Endurance360 CompleteRather not source each ingredient separately? Complete creatine, beta-alanine, rhodiola, and cordyceps stack in one tub. Requires a 3-4 week loading period; start in a base block, not race week. Also effective for leg cramp prevention.Shop Endurance360 →
- L-Citrulline Malate 2:1The blood-flow backbone. About $0.02/g vs the markup in branded tubs.View on Amazon →
- Caffeine + L-TheanineThe cleanest stim pairing. Capsules if you would rather not weigh powder.View on Amazon →
- Beta-alanine powderFor the power-buffer layer. Best taken daily, not only pre-session.View on Amazon →
- Sodium citrate powderA gut-friendly bicarbonate-style buffer for hard interval days.View on Amazon →
- 0.1g digital scaleEssential for dosing caffeine and the gram-level actives accurately.View on Amazon →
As an Amazon Associate we earn from qualifying purchases.
Dialing in caffeine?
Caffeine Calculator
Race-day dose, timing, and jitter risk for your body weight.
Fueling the session?
DIY Sports Drink Calculator
Maltodextrin and fructose race fuel with an osmolarity check.
DIY pre-workout FAQ
What is a DIY pre-workout for endurance athletes?
A DIY pre-workout is a single-serving mix of bulk ingredients tuned to a training goal rather than a generic stimulant tub. For endurance, the backbone is dietary nitrate (beetroot) plus L-citrulline malate for blood flow and oxygen economy, with a moderate caffeine and L-theanine pairing for focus without raising heart rate. You add a power-buffer, cognitive, or fat-metabolism layer depending on the session, and it costs a fraction of a branded pre-workout.
Is a homemade pre-workout cheaper than buying one?
Yes. An oxygen-economy serving of Beetroot Pro, 8g citrulline malate, 100mg caffeine, and 200mg L-theanine costs under two dollars a serving, versus about $2.40 for a commercial pre-workout like Transparent Labs BULK. Training 8 hours a week, that is roughly $160 a year saved, and you control exactly what goes in. Beetroot Pro is the one branded component; the rest are cheap bulk powders.
How much caffeine should be in an endurance pre-workout?
For aerobic work, 100 to 200mg of caffeine is the useful range, well below the 300mg-plus doses in bodybuilding pre-workouts. The goal is lower perceived effort and sharper focus without spiking heart rate during steady efforts. Pair caffeine with L-theanine at a 1:2 ratio (for example 100mg caffeine to 200mg theanine) to blunt the jitters while keeping the alertness.
Why take beetroot two hours before instead of with everything else?
Dietary nitrate has to be converted to nitric oxide by bacteria in your mouth and then by your body, a process that takes 60 to 120 minutes to peak. That is why the beetroot dose sits in its own 120-minute window, while citrulline, caffeine, and theanine all mix into a single serving 45 minutes before you start.
What is the beta-alanine tingle and is it safe?
Beta-alanine causes paresthesia, a harmless prickling or tingling of the skin that starts 15 to 20 minutes after dosing and fades within an hour. It is not an allergic reaction or a sign of anything wrong. If it bothers you, split the dose or lower it. Beta-alanine works by raising muscle carnosine over weeks, so it helps most when taken daily, not only before a session.
What does L-citrulline malate actually do?
L-citrulline raises blood arginine more effectively than arginine itself, boosting nitric oxide and blood flow for a better pump and oxygen delivery. The malate portion is a Krebs-cycle intermediate that supports aerobic energy production. Endurance doses run 6 to 8g, with the higher end used for longer events. It is very sour, so most people mask it with a flavor packet.
Save this recipe
Keep this mix in your account to revisit and tweak, or share it with a training partner.
Sign in to saveSee also: caffeine timing for endurance athletes.
Feedback
Missing something?
Tell us what you'd like to see added to this tool.
Free race-fueling tips in your inbox
New calculators and race-day fueling guides, plus first word when the printable recipe card lands.