Best Supplements to Boost Gym Endurance and Performance

Key Takeaways

1. L-Citrulline tops the list, boosting reps by 53% and endurance by 12% through superior nitric oxide production over arginine.
2. Creatine increases power output and muscle growth by rapidly replenishing phosphocreatine energy stores.
3. Beta-alanine buffers lactic acid, delaying fatigue in high-intensity sets that last 1 to 4 minutes.
4. Caffeine lowers perceived exertion and sharpens focus at doses of 3 to 6 mg per kg of body weight.
5. Choose Bucked Up’s clinically dosed L-Citrulline to upgrade pumps, endurance, and recovery in every training session.

Top 8 Proven Supplements for Gym Endurance and Performance

#1 L-Citrulline: Nitric Oxide Leader for 53% More Reps

L-Citrulline stands as the most effective nitric oxide booster for gym endurance, delivering results that direct arginine cannot match. Arginine breaks down heavily in the liver, while L-Citrulline bypasses this first-pass metabolism and converts to arginine in the kidneys. This process creates higher and more sustained nitric oxide production.

Eight grams of Citrulline Malate increased repetitions to failure by 53% across multiple sets, and endurance athletes saw 12% longer cycling times before exhaustion. These benefits come from better oxygen delivery to working muscles and improved ammonia removal through the urea cycle.

#2 Creatine: Daily Power and Strength Base

Creatine remains the most researched supplement for strength and power. Creatine supplementation enhances performance in high-intensity exercises requiring strength and power, leading to more muscle growth when combined with resistance training and faster recovery.

The phosphocreatine system supplies instant energy for explosive movements, so creatine helps you maintain power across repeated sets. Loading phases can speed up muscle saturation, but consistent daily maintenance dosing reaches the same endpoint over time.

#3 Beta-Alanine: Support Against Lactic Acid Burn

Beta-alanine delays muscular fatigue by buffering the acid buildup that occurs during intense exercise. It raises muscle carnosine levels, which neutralize hydrogen ions that contribute to burning sensations and reduced force output.

The familiar tingling feeling, called paresthesia, signals that you have reached an effective dose. Benefits usually appear after 2 to 4 weeks of daily use. Beta-alanine works best for efforts lasting 1 to 4 minutes, which fits many resistance training sets and conditioning intervals.

#4 Caffeine: Energy, Focus, and Drive Booster

Caffeine supplementation shows benefits in aerobic, anaerobic, and team sport performance, including reduced perceived exertion in men and women. Effective doses typically range from 3 to 6 mg per kg of body weight, taken 30 to 45 minutes before training.

Caffeine works by blocking adenosine receptors, increasing endorphin release, and improving neuromuscular function. High doses can narrow blood vessels, which may blunt pumps. Pairing caffeine with L-Citrulline helps maintain blood flow while still delivering strong energy and focus.

#5 Nitrates: Support for Oxygen Efficiency

Nitrates from beetroot juice provide positive ergogenic effects, especially in endurance exercise. They convert to nitric oxide through a pathway that differs from L-Citrulline, so both can work together.

Beetroot-based nitrates improve oxygen efficiency, allowing muscles to produce the same power with less oxygen. This effect supports longer efforts and delays fatigue during extended training sessions or cardio blocks.

#6 Protein and Carbohydrates: Fuel for Recovery and Next-Day Performance

Protein and carbohydrate timing around workouts supports muscle repair and glycogen refilling. These nutrients may not directly boost performance during a single session, yet they strongly influence how well you recover and train later.

Pre-workout carbohydrates help stabilize blood glucose and keep energy steady. Post-workout protein stimulates muscle protein synthesis and supports growth. Together, they help you show up stronger for your next workout.

#7 Electrolytes: Hydration and Cramp Control

Electrolyte balance becomes crucial during hard training, especially in the heat. Losing sodium, potassium, and magnesium through sweat can impair muscle function and raise cramp risk.

Replacing electrolytes supports fluid balance, nerve signaling, and muscle contraction. This matters most during long sessions, high-sweat workouts, or days with more than one training block.

#8 Bucked Up Pre-Workout Stacks: Clinical Doses, Clear Labels

Bucked Up focuses on evidence-based pre-workout formulas that use effective doses instead of underdosed proprietary blends. Their products feature clinical levels of L-Citrulline, supported by Astragin® to improve absorption.

The lineup fits different experience levels and stimulant needs. Bucked Up Pre-Workout offers 6 g of Citrulline Malate. Woke AF keeps the same 6 g of Citrulline Malate and adds 333 mg of caffeine for heavy stim users. Mother Bucker uses 4 g of Pure L-Citrulline plus Nitrosigine® and Hydroprime® for a powerful pump and hydration stack.

Explore Bucked Up’s pre-workout options featuring clinical doses of Citrulline Malate and Pure L-Citrulline to support peak performance.

Best Bucked Up Stacks for Gym Endurance

Smart stacking combines ingredients that work well together while avoiding overlap. Pre-workouts stack L-citrulline (4g) with caffeine (300mg), betaine anhydrous (1.5g), and other stimulants for NO production, pumps, energy, focus, strength, and endurance.

Bucked Up stands out by avoiding proprietary blends and listing every dose clearly. Astragin® supports citrulline absorption, so you get the full benefit of each gram on the label. The 2:1 Citrulline Malate ratio supplies both vasodilation from citrulline and energy support from malic acid in the Krebs cycle.

Dosages, Timing, and Safety Guidelines

Correct dosing and timing help you get results while limiting side effects. High-dose citrulline malate in pre-workout stacks increases NO levels, improves exercise performance, and reduces muscle soreness, though NO increasers can dangerously drop blood pressure, especially with heart conditions or BP medications.

Clinical trials using doses of 2–6 g/day of L-citrulline reported modest improvements in performance metrics, while higher doses may cause gastrointestinal discomfort. Anyone using blood pressure medications should talk with a healthcare professional before taking nitric oxide boosters.

Frequently Asked Questions

L-Citrulline vs Arginine for Gym Endurance

L-Citrulline outperforms arginine for gym endurance because it has better bioavailability. Arginine breaks down extensively in the liver, which reduces how much reaches your bloodstream. L-Citrulline bypasses this step and converts to arginine in the kidneys, raising plasma arginine and supporting steady nitric oxide production. The result is stronger pumps and better endurance than direct arginine use.

Best Bucked Up Pre-Workout for Stamina

Bucked Up pre-workout stacks deliver a strong mix of stamina-focused ingredients at clinical doses. The core Bucked Up Pre-Workout provides 6 g of Citrulline Malate at a 2:1 ratio for sustained blood flow. Woke AF keeps that pump support and adds higher stimulants for intense energy. Mother Bucker suits advanced users by combining Pure L-Citrulline with Nitrosigine® and Hydroprime® for maximum vasodilation and cellular hydration.

Gym Supplements with Real Science Behind Them

The most supported supplements for gym performance include L-Citrulline, creatine, beta-alanine, and caffeine. L-Citrulline can deliver 53% more reps, creatine improves power output, beta-alanine buffers lactic acid, and caffeine reduces perceived effort. Nitrates from beetroot and solid electrolyte intake add extra benefits. Avoid products that hide ingredient amounts behind proprietary blends.

Supplements That Increase Gym Performance the Most

L-Citrulline provides the largest performance jump for many lifters, with research showing up to 53% more reps to failure and 12% longer endurance. Creatine ranks next for strength and power work. Combining L-Citrulline with caffeine supports both pump and energy in the same session. Beta-alanine completes the core stack by delaying fatigue during intense sets.

Best Time to Take L-Citrulline Before a Workout

Take L-Citrulline about 60 minutes before training for the strongest effect. This window allows absorption and conversion to arginine in the kidneys, which supports nitric oxide production as your workout begins. Peak blood levels appear between roughly 0.7 and 2 hours after ingestion, so the 60-minute mark lines up well with most gym sessions.

Conclusion: Use L-Citrulline and Bucked Up to Push New PRs

The best supplements to boost gym endurance and performance rely on proven mechanisms and clinical doses, not flashy marketing. L-Citrulline leads this group by driving nitric oxide production and endurance gains that can turn average workouts into PR-setting days.

Thoughtful stacking multiplies these effects, and Bucked Up formulas make that process simple. Their transparent labels, clinical dosing, and absorption support give you a reliable mix of L-Citrulline and other performance enhancers in every scoop.

Bucked Up promotes a clinical dosing of science-backed ingredients, including Citrulline Malate and Pure L-Citrulline. Find the L-Citrulline option that fits your routine and unlock your peak performance.