The OLEUS Pre-Activity Shot is a natural-source endurance formula built around named active ingredients at published doses. No proprietary blends. No hidden quantities. No filler ingredients dressed up as performance compounds. Turn the bottle around, and you can read every milligram, look up the research, and decide for yourself.
Most pre-workout products on the shelf do the opposite. They hide individual doses inside "proprietary blends" lean on isolated stimulants designed for 45-minute gym sessions, and load the label with names that sound impressive without the doses to back them. This is a different approach: a multi-active cellular stack drawn from natural sources, dosed to support endurance over hours rather than minutes. Here is every ingredient in the OLEUS Pre-Activity Shot, what it does inside your cells, and the published evidence behind it. For the broader science of plant-based antioxidants for endurance athletes, the antioxidants guide is the place to start.
What is in the OLEUS Pre-Activity Shot?
The Pre-Activity Shot is a 60 ml liquid formula with the headline compounds: Oleuropein (from olive leaf extract), L-citrulline, Acetyl-L-carnitine, Caffeine (from Guarana), Magnesium, a full B-vitamin complex, and Vitamin C (from Acerola). Every dose is printed on the label.
Each compound earns its place. Below, the main ingredient sections, grouped by function. Every ingredient sits inside the 60-minute pre-training window when the shot is taken.
Why Oleuropein, and not a synthetic stimulant?
Oleuropein is a polyphenol extracted from olive leaves. It supports mitochondrial function, helps manage oxidative stress, and is the compound at the centre of the OLEUS formula. Unlike stimulants that mask fatigue, Oleuropein supports the cellular machinery that produces energy in the first place.
The compound came out of research at the University of Lausanne, where scientists screened thousands of plant compounds for their effect on cellular energy production. Oleuropein stood out for its action on the mitochondria, the structures inside every cell that produce roughly 90% of the ATP your muscles use during endurance exercise. For the underlying biology, the Mitochondria Guide covers what happens at the cellular level.
The Pre-Activity Shot contains 100 mg of Oleuropein per shot. This dose was selected to match the levels used in the OLEUS placebo-controlled trial with 28 cyclists from a Switzerland-based World Tour professional cycling team, which showed +25% sustained power output over a multi-day endurance protocol compared to placebo. For a deeper look at the research, the Olive Leaf Extract article walks through the studies.
"We did not start with a marketing brief. We started with a question: which compounds actually support how the cell produces energy under endurance load? Oleuropein answered that question better than anything else we screened."
OLEUS Performance Lab
Why L-citrulline and Acetyl-L-carnitine together?
L-citrulline and Acetyl-L-carnitine sit at two different points in the energy delivery chain. Citrulline raises nitric oxide, which dilates blood vessels and improves the delivery of oxygen and fuel to working muscle. Carnitine moves fatty acids into the mitochondria where they can be burned for energy. Together, they support both the delivery of fuel and its conversion into ATP.
L-citrulline converts to L-arginine in the kidneys, which is then converted to nitric oxide. Nitric oxide relaxes the smooth muscle in blood vessel walls, increasing blood flow and improving oxygen delivery during exercise. Research published in the Journal of the International Society of Sports Nutrition found that L-citrulline supplementation improved cycling time trial performance and reduced muscle fatigue ratings in trained men. The shot contains 885 mg of L-citrulline.
Acetyl-L-carnitine plays a different role. Inside muscle cells, the Carnitine shuttle is what allows long-chain fatty acids to cross into the mitochondria for oxidation. For endurance efforts lasting more than 90 minutes, fat oxidation becomes a significant contributor to total energy production. Research in The Journal of Physiology, has shown that increasing muscle Carnitine content can alter fuel utilisation during exercise. The shot contains 375 mg of Acetyl-L-carnitine.
How much caffeine is in the Pre-Activity Shot, and why from guarana?
The Pre-Activity Shot contains 80 mg of caffeine, delivered through Guarana extract. Guarana is a Brazilian climbing plant whose seeds naturally contain caffeine in a plant matrix that releases more slowly than isolated caffeine powder. The result is a gentler activation curve, fewer peaks and crashes, and a dose that does not overwhelm the gut over a long session.
Caffeine works by blocking adenosine receptors in the brain. Adenosine is one of the molecules that signals "you are tired." Block its receptors, and you delay the feeling of fatigue. The established ergogenic range for endurance is 3 to 6 mg per kg of body weight, taken 45 to 60 minutes before exercise, according to the International Society of Sports Nutrition position stand on caffeine. The 80 mg in the shot sits below that range deliberately.
Most commercial pre-workouts use 250 to 400 mg of caffeine per serving. That dose is designed for short, high-intensity gym sessions where side effects do not have time to surface. For a four-hour ride or a marathon, that level of caffeine almost guarantees GI distress, accelerated dehydration, and a hard crash. The 80 mg dose is calibrated for endurance, not for a 45-minute lifting session, and it sits comfortably alongside a coffee or an on-course gel later in the effort.
Why magnesium and a full B-vitamin complex?
Magnesium and the B-vitamins are the enzymatic cofactors that the rest of the formula depends on. Every molecule of ATP that powers your muscles requires magnesium to be biologically active. Every step in the breakdown of carbohydrates, fats, and amino acids into usable energy requires one or more B-vitamins. Skip these, and the rest of the stack works at reduced capacity.
Magnesium acts as a cofactor in more than 300 enzymatic reactions in the body, with ATP synthesis at the centre of that list. Endurance athletes are particularly prone to Magnesium loss: research published in Magnesium Research indicates that sweat losses during prolonged exercise can deplete 10 to 20% of daily Magnesium intake per session. The shot contains 56.25 mg of Magnesium, which is 15% of the recommended daily intake, delivered at the moment your cells need it most.
The B-vitamin complex covers six of the energy metabolism cofactors at 50% of the recommended daily intake each: B1 (thiamine, 1.10 mg) for carbohydrate metabolism, B2 (riboflavin, 1.25 mg) as an electron transport chain cofactor, B3 (niacin, 0.55 mg) for NAD+ synthesis, B5 (pantothenic acid, 3 mg) for coenzyme A, B6 (pyridoxine, 0.70 mg) for amino acid metabolism, and B12 (cyanocobalamin) for red blood cell production. These are the dose levels that support sustained training, not therapeutic mega-doses, which is the right call for a daily-use pre-activity formula.
What about vitamin C and electrolytes?
The shot delivers 40 mg of vitamin C from Acerola extract, plus 27.5 mg of sodium for electrolyte support. Acerola is a Caribbean cherry with one of the highest natural Vitamin C concentrations of any fruit. Using a natural source means the Vitamin C arrives alongside the plant's co-factors and bioflavonoids, which support absorption.
Vitamin C is the most well-known antioxidant, but its role in endurance sport goes beyond general antioxidant support. It supports collagen synthesis (relevant to tendons and connective tissue), iron absorption (a known weak point for endurance athletes, particularly female runners and cyclists), and the regeneration of other antioxidants in the body. Endurance athletes deplete Vitamin C 30 to 50% faster than sedentary controls, according to data summarised in Sports Medicine.
Sodium is there to support the cellular machinery the rest of the formula activates, and to begin priming the electrolyte balance you will continue to manage on course.
Why does the dose of each ingredient matter?
Proprietary blends are the central problem with most pre-workout labels. When a product lists "Endurance Performance Blend: 2,500 mg" with seven ingredients inside the blend, you cannot know how much of any single ingredient you are getting. The first ingredient takes up most of the 2,500 mg. The last ingredient might be present in symbolic amounts. The label tells you nothing.
Every named active ingredient in the Pre-Activity Shot is listed individually with its exact dose. The formula prioritises a complete cellular stack over mega-dosing any single compound, which is the right design for an endurance product taken before sessions lasting hours, not minutes. The same principle runs through the rest of the OLEUS approach to natural versus synthetic pre-workouts: the formula is the argument.
What does the clinical research show?
The OLEUS formula was evaluated in a placebo-controlled trial with 28 cyclists from a Switzerland-based World Tour professional cycling team. The protocol involved a multi-day endurance test, comparing the Oleuropein-based formula against a placebo across sustained power output, perceived exertion, and recovery markers.
The riders taking the formula showed +25% sustained power output over the test period compared to the placebo group. This is the clinical foundation underneath the product. It is not extrapolation from a single ingredient study. It is the actual formula tested in actual athletes under controlled conditions.
Frequently asked questions
Is the Pre-Activity Shot safe to use every day?
The shot is formulated for use before training and racing, not as a daily supplement. The caffeine content, in particular, is best reserved for sessions where you want the activation benefit. For everyday cellular support, the Daily Shot is the foundation. For race blocks and key training sessions, the Pre-Activity Shot stacks on top.
Does it contain sugar?
Yes. Each 60 ml shot contains 19.3 g of carbohydrates, of which 18 g are sugars from sucrose, delivering 84 kcal. This is part of the design: the carbohydrates serve as immediate pre-activity fuel, and they also support the L-citrulline conversion pathway. If you are tracking race-week carbohydrates, count the shot as a small pre-race fuel source, not a zero-calorie supplement.
Can I take it with coffee?
You can, but you do not need to. The 80 mg of caffeine in the shot is roughly equivalent to a small espresso. Stacking with coffee can push total intake into the 200 to 300 mg range, which is fine for most athletes but worth knowing.
How long before exercise should I take it?
Take the shot 45 to 60 minutes before activity. This is the window in which caffeine absorption peaks, Oleuropein and the antioxidant compounds are in circulation, and L-citrulline has converted into the nitric oxide pathway. The full guide to the 60-minute pre-training window covers the protocol in detail.
Is it tested for banned substances?
The formula is manufactured in Switzerland under standards aligned with European supplement regulation. Each batch is tested for contaminants. For competitive athletes who need formal sport-certification documentation, contact the OLEUS team for the most current batch certificates.
Will it work without the Daily Shot?
The Pre-Activity Shot delivers acute performance benefits on its own. The Daily Shot supports the cellular foundation that the Pre-Activity Shot then activates. Athletes who use both report stronger, more consistent training blocks than those who use only the Pre-Activity Shot before sessions.
The bottom line
Independently named ingredients. Every dose printed. A natural-source, full-spectrum stack designed for endurance, not for a 45-minute gym session. The Pre-Activity Shot was built so that an endurance athlete who reads the label can find the science behind every milligram. That is the formula.
Sources
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Goldstein, E.R., Ziegenfuss, T., Kalman, D., Kreider, R., Campbell, B., Wilborn, C., Taylor, L., Willoughby, D., Stout, J., Graves, B.S., Wildman, R., Ivy, J.L., Spano, M., Smith, A.E., Antonio, J. (2010). International Society of Sports Nutrition position stand: caffeine and performance. Journal of the International Society of Sports Nutrition, 7(1), 5.
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Suzuki, T., Morita, M., Kobayashi, Y., Kamimura, A. (2016). Oral L-citrulline supplementation enhances cycling time trial performance in healthy trained men: Double-blind randomized placebo-controlled 2-way crossover study. Journal of the International Society of Sports Nutrition, 13, 6.
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Bailey, S.J., Blackwell, J.R., Lord, T., Vanhatalo, A., Winyard, P.G., Jones, A.M. (2015). L-Citrulline supplementation improves O2 uptake kinetics and high-intensity exercise performance in humans. Journal of Applied Physiology, 119(4), 385-395.
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Stephens, F.B., Constantin-Teodosiu, D., Greenhaff, P.L. (2007). New insights concerning the role of carnitine in the regulation of fuel metabolism in skeletal muscle. The Journal of Physiology, 581(2), 431-444.
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Wall, B.T., Stephens, F.B., Constantin-Teodosiu, D., Marimuthu, K., Macdonald, I.A., Greenhaff, P.L. (2011). Chronic oral ingestion of L-carnitine and carbohydrate increases muscle carnitine content and alters muscle fuel metabolism during exercise in humans. The Journal of Physiology, 589(4), 963-973.
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NIH Office of Dietary Supplements. Magnesium: Fact Sheet for Health Professionals. ods.od.nih.gov
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NIH Office of Dietary Supplements. Vitamin C: Fact Sheet for Health Professionals. ods.od.nih.gov
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NIH Office of Dietary Supplements. B-Complex Vitamins: Fact Sheets for Health Professionals. ods.od.nih.gov
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Nielsen, F.H., Lukaski, H.C. (2006). Update on the relationship between magnesium and exercise. Magnesium Research, 19(3), 180-189.
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Peake, J.M. (2003). Vitamin C: effects of exercise and requirements with training. International Journal of Sport Nutrition and Exercise Metabolism, 13(2), 125-151.
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OLEUS placebo-controlled trial, 28 cyclists, Switzerland-based World Tour team, multi-day endurance protocol. Data on file, OLEUS Performance Lab.
