Progress your training gradually and include enough recovery between demanding sessions. Combine strength, aerobic activity, and mobility according to your goals, with a consistent sleep routine to support the work.

Fitness
Fitness is the ability to meet physical demands and recover well enough to keep progressing. It brings together strength, endurance, movement quality, and the confidence to take part in activities you enjoy. Whether you are establishing a routine or improving a specific performance, a clear goal gives your efforts direction. The support needed depends on the work involved. Short, intense efforts place different demands on the body from prolonged activity, while repeated training also requires attention to muscle repair, connective tissue, and fluid balance. Targeted nutrition can help meet these demands and make a well-designed training routine easier to sustain. Useful progress shows up in the activity itself. Completing more quality repetitions, maintaining a comfortable pace, or recovering more reliably between sessions can each represent a worthwhile improvement. Choosing the outcome that matters most to you helps distinguish essential support from additions that have little relevance to your training.
Warnings
- Count all stimulants: Count caffeine from drinks and supplements together. Review intake if you notice jitteriness, palpitations, anxiety, or disrupted sleep.
- Kidney disease changes supplement safety: Kidney function affects how the body handles several minerals and other ingredients. Seek individual advice before adding products, especially potassium or magnesium, if you have kidney disease or relevant medicines.
- Match fluids to your needs: Adjust fluids to your activity, the weather, and any health-related guidance. Both too little and excessive intake can cause problems.
- Avoid overlapping high doses: Count nutrients from multivitamins, individual supplements, and fortified products together. Keep the combined amounts within appropriate limits for your circumstances.
Goal guidance
Eat enough for your training, with protein across the day and carbohydrates suited to the workload. Plan fluids around session length, conditions, and how much you sweat.
Active adults working toward stronger lifts, better stamina, improved recovery, or a more consistent training routine.
Get individual advice with cardiovascular or kidney conditions or medicines affecting fluid balance. Check stimulant totals and product quality; persistent exercise-related pain, dizziness, or unusual breathlessness needs assessment.
Some ingredients support an individual session, while strength and endurance develop through consistent training over weeks and months. Compare similar workouts to see how you are progressing.
A demanding program needs enough food, sleep, and recovery to remain productive. Introduce supplements one at a time and avoid treating a strong stimulant sensation as a measure of workout quality.
Ingredients
Creatine increases phosphocreatine stores in muscles, which aids in the rapid regeneration of ATP, the primary energy currency of the cell. This leads to tangible improvements in strength, power output, and the ability to perform more repetitions during resistance training.
- Focuses on
- Most relevant for
- Individuals performing resistance training or repetitive, high-intensity sports aiming to maximize strength and muscle growth.
Potential benefits
- Enhanced Strength and Power.Significantly improves performance in multi-joint compound lifts, such as the bench press and squat, when combined with regular resistance training.
- Improved Anaerobic Capacity.Increases the ability to perform repeated bouts of short-duration, high-intensity activity, including sprinting and explosive jumping.
- Support for Lean Mass.Promotes increases in fat-free muscle mass, with evidence suggesting particularly strong responses in individuals with lower baseline muscle creatine, such as vegetarians.
Limitations
- Limited Aerobic Benefit.Evidence shows no reliable improvement in sustained endurance performance and potential negative effects on maximal oxygen uptake (VO2max).
- Population Variability.Ergogenic effects appear most consistent in younger males, while findings in females and older adults are more heterogeneous and often show smaller gains.
- Impact of Weight Gain.Increases in total body mass, often due to water retention, may be counterproductive in sports where a lower weight-to-power ratio is critical.
Things to consider
Initial increases in body weight are common due to cellular water retention; athletes in weight-class-specific sports should monitor mass changes closely.
Study evidence
143 studiesCreatine can improve strength, power, and gains in lean mass, particularly alongside resistance training or repeated high-intensity exercise. Benefits vary by activity and population, and it does not reliably improve aerobic endurance; increases in body mass may also matter in weight-sensitive sports.
Magnesium participates in over 300 enzymatic reactions, including glycolysis and ATP synthesis. Ensuring adequate levels can prevent cramping, improve sleep quality for better recovery, and support overall metabolic and cardiovascular health under physical stress.
- Focuses on
- Most relevant for
- Older adults or individuals with low dietary magnesium intake looking to support muscle mass and preserve physical function.
Potential benefits
- Perceived Recovery Support.Magnesium supplementation may help reduce muscle soreness and lower the rating of perceived exertion following intense eccentric exercise.
- Physical Function in Aging.Higher magnesium intake is associated with better muscle power, mass, and physical performance scores in older populations, particularly women.
- Maintenance of Work Capacity.Correcting marginal magnesium deficiency can prevent increased oxygen requirements and declines in endurance performance during physical activity.
Limitations
- Ineffective for Sufficient Status.Evidence suggests that for athletes and active individuals with adequate magnesium levels, supplementation does not reliably enhance strength or power.
- Potential Performance Decline.Short-term high-dose intake of magnesium chloride has been linked to modest decreases in VO2max and sprint power in non-deficient exercisers.
- Ineffective Topical Delivery.Topical magnesium gels have not demonstrated the ability to reduce muscle damage markers or soreness compared to placebo treatments.
Things to consider
Excessive intake can cause gastrointestinal distress or laxative effects. Supplementation is generally not recommended for regular exercisers who already maintain adequate magnesium levels.
Study evidence
29 studiesMagnesium research shows mixed findings for exercise performance and recovery, with no consistent advantage established for healthy people whose magnesium status is adequate. Positive signals in some settings coexist with neutral and occasionally unfavourable findings.

Milk protein contains both whey and casein, offering a blend of fast- and slow-digesting proteins. This combination provides a rapid spike in amino acids to initiate muscle protein synthesis post-workout, followed by a sustained release to reduce muscle breakdown for hours.
- Focuses on
- Most relevant for
- Individuals seeking a blend of fast- and slow-digesting proteins to support muscle maintenance and recovery after exercise.
Potential benefits
- Muscle Protein Synthesis.Unconfirmed. The combination of whey and casein proteins is intended to provide both immediate and sustained amino acids for muscle building, though this benefit is unproven here as no direct research was supplied.
- Post-Exercise Recovery.Unconfirmed. Milk protein is designed to supply the essential amino acids necessary for repairing muscle tissue after physical exertion, but its specific effectiveness for fitness outcomes remains unconfirmed in this context.
Limitations
- Lack of Direct Evidence.No clinical research or study summaries were provided to verify the specific impact of milk protein on fitness goals.
- Individual Variability.The effectiveness of protein supplementation depends heavily on an individual's total daily protein intake and the intensity of their exercise regimen.
Things to consider
Contains dairy and lactose, which may cause digestive distress for individuals with milk allergies or lactose intolerance.
Study evidence
No published studies for this goal yet.
Vitamin D functions as a steroid hormone, playing a key role in muscle function and strength. Widespread deficiency can impair athletic performance, and supplementation to optimal levels supports the body's foundational systems for training and adaptation.
- Focuses on
- Most relevant for
- Active individuals with low vitamin D levels seeking to support muscle recovery and maintain baseline physical function.
Potential benefits
- Post-Exercise Recovery.Evidence suggests that supplementation may help improve the recovery of skeletal muscle force following intense or muscle-damaging exercise in active adults with sufficient status.
- Lower-Body Strength Support.While overall strength gains are inconsistent, some research in athletes and older adults indicates vitamin D may specifically support quadriceps strength and lower-limb mobility.
- Physical Function Maintenance.Correcting a deficiency is associated with better physical performance scores in older populations, although increasing levels beyond sufficiency does not reliably boost fitness.
Limitations
- Inconsistent Performance Gains.Multiple meta-analyses in athletes and healthy adults show no significant overall improvement in maximum strength, power, or anaerobic performance even after reaching sufficient blood levels.
- Limited Athletic Enhancement.Benefits found in elderly or sedentary individuals with severe deficiencies often do not translate to performance boosts for well-trained athletes with adequate baseline status.
- Potential Performance Decline.Certain high-dose regimens have been associated with unexpected decreases in handgrip and leg strength in some studies, indicating that excessive intake may be counterproductive.
Things to consider
High intermittent doses in older adults have been linked to an increased risk of falls. Some trials using moderately high daily doses in women reported a reduction in muscle strength and physical performance.
Study evidence
163 studiesVitamin D supplementation does not reliably improve fitness, strength, or exercise performance, even though low blood levels are often associated with poorer function. Benefits occur in some groups and outcomes, but raising levels alone does not guarantee improvement, and some regimens have worsened performance or increased falls.
Enhanced nitric oxide production from Arginine leads to increased blood flow to working muscles during exercise. This improved circulation facilitates better delivery of oxygen and nutrients, while simultaneously aiding in the removal of metabolic byproducts like lactic acid. The result can be enhanced endurance, reduced fatigue, and improved overall athletic performance and recovery.
- Focuses on
- Most relevant for
- Recreational exercisers or those starting a fitness routine, as benefits are less consistent in highly trained athletes.
Potential benefits
- Aerobic Capacity Support.Meta-analyses indicate that arginine may increase VO2 max and improve aerobic performance, potentially by reducing the oxygen cost of exercise in healthy individuals.
- Anaerobic Power.Some evidence suggests small improvements in anaerobic work capacity and power, though these effects are often less pronounced than aerobic gains and vary by sport.
- Oxidative Metabolism.Supplementation may improve the metabolic response to exercise, such as lowering lactate-to-speed ratios and increasing glucose clearance, which supports efficient fuel use.
Limitations
- Limited for Elite Athletes.Research consistently shows that while untrained or moderately active individuals may see benefits, highly trained athletes often experience no performance enhancement.
- Unreliable Strength Gains.Multiple controlled trials found that arginine fails to significantly improve maximum strength, peak torque, or total repetitions during resistance training.
- Non-Translational Blood Flow.While arginine can increase muscle blood volume and nitric oxide markers, these physiological changes do not always lead to measurable improvements in exercise performance.
Things to consider
Oral intake can cause gastrointestinal distress, including stomach cramping, abdominal fullness, and bloating, particularly at doses used in performance studies.
Study evidence
23 studiesArginine has mixed evidence for improving fitness: pooled research suggests possible benefits for exercise capacity, but many trials show no improvement in strength or endurance, particularly in trained athletes. Changes in blood flow or metabolism do not consistently translate into better performance.
Intense training is a physical stressor that elevates cortisol. Ashwagandha helps the body adapt to this stress, leading to better hormonal balance, reduced feelings of fatigue, and improved sleep quality, which are all fundamental for optimal physical recovery and progress.
- Focuses on
- Most relevant for
- Physically active individuals and athletes looking to enhance strength gains and cardiorespiratory endurance during structured training programs.
Potential benefits
- Strength Gains.Supplementation alongside resistance training is linked to significantly greater increases in muscle strength and size compared to exercise alone.
- Aerobic Capacity.Unconfirmed. Evidence points to improved VO2 max and endurance performance in several trials, although results are inconsistent in high-intensity training environments.
- Recovery Support.May help lower markers of exercise-induced muscle injury, such as creatine kinase, and improve perceived recovery scores after strenuous training.
Limitations
- Variable Endurance Impact.Benefits to aerobic capacity are inconsistent; some trials in elite wrestlers and athletes performing HIIT show no improvement beyond the effects of training.
- Limited Weight Loss Evidence.Meta-analytic data suggests that supplementation does not reliably reduce body weight or body fat percentage despite its role in muscle growth.
- Extract Consistency.Differences in the specific extracts and doses used across studies make it difficult to determine the optimal preparation for specific fitness outcomes.
Study evidence
23 studiesAshwagandha may improve strength gains alongside resistance training and may support aerobic fitness. Benefits vary across studies, however, and some controlled research finds no added improvement in endurance beyond training alone; effects on body fat are also inconsistent.
Studies
Explore published research for this goal.
Sources
Up to five highest-ranked published examples per ingredient. Study counts and charts include all published studies for the connection.
- Creatine in combination with resistance training and improvement in muscle strength: evaluation of a health claim pursuant to Article 13(5) of Regulation (EC) No 1924/2006.
- Effect of creatine and weight training on muscle creatine and performance in vegetarians.
- Long-term creatine intake is beneficial to muscle performance during resistance training.
- Effects of Combined Versus Single Supplementation of Creatine, Beta-Alanine, and L-Citrulline During Short Sprint Interval Training on Basketball Players' Performance: A Double-Blind Randomized Placebo-Controlled Trial.
- The Additive Effects of Creatine Supplementation and Exercise Training in an Aging Population: A Systematic Review of Randomized Controlled Trials.
- Total magnesium intake and risk of frailty in older women.
- Dietary Magnesium May Be Protective for Aging of Bone and Skeletal Muscle in Middle and Younger Older Age Men and Women: Cross-Sectional Findings from the UK Biobank Cohort.
- Dietary Magnesium Is Positively Associated With Skeletal Muscle Power and Indices of Muscle Mass and May Attenuate the Association Between Circulating C-Reactive Protein and Muscle Mass in Women.
- Nutritional intake as a determinant of high-speed resistance and multicomponent training efficacy on strength in older women at risk of sarcopenia. A randomized clinical trial.
- Minerals and Sarcopenia in Older Adults: An Updated Systematic Review.
- Effect of Calcifediol on Physical Performance and Muscle Strength Parameters: A Systematic Review and Meta-Analysis.
- Effects of vitamin D supplementation on upper and lower body muscle strength levels in healthy individuals. A systematic review with meta-analysis.
- Influence of Sunlight and Oral D3 Supplementation on Serum 25(OH)D Concentration and Exercise Performance in Elite Soccer Players.
- Effects of Vitamin D Supplementation in Elite Athletes: A Systematic Review.
- Association between serum vitamin D levels and cardiorespiratory fitness in the adult population of the USA.
- The effect of L-arginine supplementation on maximal oxygen uptake: A systematic review and meta-analysis.
- L-Arginine Enhances the Effects of Cardiac Rehabilitation on Physical Performance: New Insights for Managing Cardiovascular Patients During the COVID-19 Pandemic.
- THE EFFECT OF A SINGLE ORAL DOSE OF L-ARGININE ON QUADRICEPS STRENGTH IN SMOKERS AND NON-SMOKERS: A NON-RANDOMIZED CLINICAL TRIAL.
- Efficacy of amino acids in sports nutrition- review of clinical evidences.
- Chronic L-arginine supplementation enhances endurance exercise tolerance in heart failure patients.
- Effects of an Aqueous Extract of Withania somnifera on Strength Training Adaptations and Recovery: The STAR Trial.
- Efficacy of Ashwagandha (Withania somnifera [L.] Dunal) in improving cardiorespiratory endurance in healthy athletic adults.
- Effects of Ashwagandha ( Withania somnifera) standardized root extract on physical endurance and VO 2max in healthy adults performing resistance training: An eight-week, prospective, randomized, double-blind, placebo-controlled study.
- Effects of Withania somnifera (L.) Dunal (Ashwagandha) on cognitive and physical function in adults: a systematic review and meta-analysis.
- Effects of eight-week supplementation of Ashwagandha on cardiorespiratory endurance in elite Indian cyclists.
- Effects of chronic betaine supplementation on performance in professional young soccer players during a competitive season: a double blind, randomized, placebo-controlled trial.
- Effects of short-term betaine supplementation on muscle endurance and indices of endocrine function following acute high-intensity resistance exercise in young athletes.
- Effects of Nutrition Interventions on Athletic Performance in Soccer Players: A Systematic Review.
- Betaine supplementation improves CrossFit performance and increases testosterone levels, but has no influence on Wingate power: randomized crossover trial.
- Effects of Betaine Supplementation on Muscle Strength and Power: A Systematic Review.
- Effect of caffeine ingestion on cycling performance: a systematic review and meta-analysis.
- Effects of Caffeine Intake on Endurance Running Performance and Time to Exhaustion: A Systematic Review and Meta-Analysis.
- Acute Effects of Caffeine Supplementation on Movement Velocity in Resistance Exercise: A Systematic Review and Meta-analysis.
- Sex Differences in the Ergogenic Response of Acute Caffeine Intake on Muscular Strength, Power and Endurance Performance in Resistance-Trained Individuals: A Randomized Controlled Trial.
- Can I Have My Coffee and Drink It? A Systematic Review and Meta-analysis to Determine Whether Habitual Caffeine Consumption Affects the Ergogenic Effect of Caffeine.
- The Effects of Combined Exercise with Citrulline Supplementation on Body Composition and Lower Limb Function of Overweight Older Adults: A Systematic Review and Meta-Analysis.
- Effect of High-Intensity Interval Training Combined with L-Citrulline Supplementation on Functional Capacities and Muscle Function in Dynapenic-Obese Older Adults.
- Initial Dietary Protein Intake Influence Muscle Function Adaptations in Older Men and Women Following High-Intensity Interval Training Combined with Citrulline.
- Effects of Citrulline alone or combined with exercise on muscle mass, muscle strength, and physical performance among older adults: a systematic review.
- Combined Vs. Single Supplementation of L-Citrulline and Sodium Bicarbonate During Sprint Interval Training in Basketball Players: Effects on Physical Performance and Hormonal Adaptations.
- Fish oil-derived n-3 PUFA therapy increases muscle mass and function in healthy older adults.
- Fish-oil supplementation enhances the effects of strength training in elderly women.
- Effects of fish oil-derived n-3 polyunsaturated fatty acid on body composition, muscle strength and physical performance in older people: a secondary analysis of a randomised, double-blind, placebo-controlled trial.
- Effects of Omega-3 Fatty Acids on Muscle Mass, Muscle Strength and Muscle Performance among the Elderly: A Meta-Analysis.
- Efficacy of Boswellia serrata Extract and/or an Omega-3-Based Product for Improving Pain and Function in People Older Than 40 Years with Persistent Knee Pain: A Randomized Double-Blind Controlled Clinical Trial.
- A systematic review and meta-analysis of propionyl-L-carnitine effects on exercise performance in patients with claudication.
- Oral acetyl-L-carnitine therapy reduces fatigue in overt hepatic encephalopathy: a randomized, double-blind, placebo-controlled study.
- Prolonged oral L-carnitine substitution increases bicycle ergometer performance in patients with severe, ischemically induced cardiac insufficiency.
- L-Carnitine treatment reduces severity of physical and mental fatigue and increases cognitive functions in centenarians: a randomized and controlled clinical trial.
- Effects of nine weeks L-Carnitine supplementation on exercise performance, anaerobic power, and exercise-induced oxidative stress in resistance-trained males.
- Taurine supplementation enhances anaerobic power in elite speed skaters: A double-blind, randomized, placebo-controlled, crossover study.
- The effect of acute taurine ingestion on 3-km running performance in trained middle-distance runners.
- Effects of different doses of taurine supplementation on repeated-sprint performance after exhaustive exercise in a high temperature and humidity environment.
- Oral taurine improves critical power and severe-intensity exercise tolerance.
- Acute taurine supplementation enhances thermoregulation and endurance cycling performance in the heat.
- Inter-individual variability in redox and performance responses after antioxidant supplementation: A randomized double blind crossover study.
- Antioxidant supplementation, redox deficiencies and exercise performance: A falsification design.
- A significant relationship between plasma vitamin C concentration and physical performance among Japanese elderly women.
- Low vitamin C values are linked with decreased physical performance and increased oxidative stress: reversal by vitamin C supplementation.
- Low dietary vitamin C intake is associated with low muscle strength among elderly Korean women.
- The Effects of 6 Weeks of Tribulus terrestris L. Supplementation on Body Composition, Hormonal Response, Perceived Exertion, and CrossFit® Performance: A Randomized, Single-Blind, Placebo-Controlled Study.
- The effect of five weeks of Tribulus terrestris supplementation on muscle strength and body composition during preseason training in elite rugby league players.
- The effects of Tribulus terrestris on body composition and exercise performance in resistance-trained males.
- Insights into Supplements with Tribulus Terrestris used by Athletes.
- Tribulus terrestris extracts alleviate muscle damage and promote anaerobic performance of trained male boxers and its mechanisms: Roles of androgen, IGF-1, and IGF binding protein-3.
- Which Protein-Based Dietary Supplements Most Effectively Enhance Fat-Free Mass and Strength Gains in Healthy Adults Undergoing Resistance Training? A Network Meta-Analysis.
- Collagen peptide supplementation in combination with resistance training improves body composition and increases muscle strength in elderly sarcopenic men: a randomised controlled trial.
- Dietary collagen peptides alleviate exercise-induced muscle soreness in healthy middle-aged males: a randomized double-blinded crossover clinical trial.
- Effects of Specific Bioactive Collagen Peptides in Combination with Concurrent Training on Running Performance and Indicators of Endurance Capacity in Men: A Randomized Controlled Trial.
- Collagen Peptide Supplementation Enhances Muscle-Tendon Stiffness and Explosive Strength: A 16-wk Randomized Controlled Trial.
- The effect of curcumin supplementation on delayed-onset muscle soreness, inflammation, muscle strength, and joint flexibility: A systematic review and dose-response meta-analysis of randomized controlled trials.
- The Effects of Curcumin Supplementation on Muscle Damage, Oxidative Stress, and Inflammatory Markers in Healthy Females with Moderate Physical Activity: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial.
- Modulation of Exercise-Induced Muscle Damage, Inflammation, and Oxidative Markers by Curcumin Supplementation in a Physically Active Population: A Systematic Review.
- Effects of Turmeric Concentrate on Cardiovascular Risk Factors and Exercise-Induced Oxidative Stress in Healthy Volunteers; an Exploratory Study.
- Effects of curcumin supplementation on sport and physical exercise: a systematic review.
- Ferric carboxymaltose in patients with heart failure and iron deficiency.
- Marginal iron deficiency without anemia impairs aerobic adaptation among previously untrained women.
- Ferric Carboxymaltose Versus Ferrous Fumarate in Anemic Children with Inflammatory Bowel Disease: The POPEYE Randomized Controlled Clinical Trial.
- Daily iron supplementation for improving anaemia, iron status and health in menstruating women.
- Altered metabolic response of iron-depleted nonanemic women during a 15-km time trial.
- Longitudinal Association Between Sodium and Potassium Intake and Physical Performance in Older Adults.
- Exercise-induced hyperkalaemia can be reduced in human subjects by moderate training without change in skeletal muscle Na,K-ATPase concentration.
- Potassium Nitrate in Heart Failure With Preserved Ejection Fraction: A Randomized Clinical Trial.
- Potassium Bicarbonate Supplementation Lowers Bone Turnover and Calcium Excretion in Older Men and Women: A Randomized Dose-Finding Trial.
- Exercise-Associated Muscle Cramps in Ironman-Distance Triathletes Over 3 Decades.
- Effects of Rhodiola rosea on Physical and Decision-Making Performance in Football Players: A Randomised Controlled Trial.
- Dose-Response Effects of Short-Term Rhodiola rosea (Golden Root Extract) Supplementation on Anaerobic Exercise Performance and Cognitive Function in Resistance-Trained Athletes: A Randomized, Crossover, Double-Blind, and Placebo-Controlled Study.
- The Effect of Short-Term Rhodiola rosea Supplementation on Simulated Game Time, Perceived Fatigue, and Performance in Basketball Players.
- Combined Rhodiola rosea and eccentric training boost endurance performance and lower-limb reactive strength in recreationally active women.
- The Impact of Rhodiola Rosea Extract on Strength Performance in Alternative Bench-Press and Bench-Pull Exercises Under Resting and Mental Fatigue Conditions: A Randomized, Triple-Blinded, Placebo-Controlled, Crossover Trial.
- Additive effects of beta-alanine and sodium bicarbonate on upper-body intermittent performance.
- Sodium Hyperhydration Improves Performance With No Change in Thermal and Cardiovascular Strain in Female Cyclists Exercising in the Heat Across the Menstrual Cycle.
- Sodium bicarbonate supplementation improves severe-intensity intermittent exercise under moderate acute hypoxic conditions.
- International Society of Sports Nutrition position stand: sodium bicarbonate and exercise performance.
- The effects of sodium bicarbonate ingestion on swimming interval performance in trained competitive swimmers.
- Association between composite dietary antioxidant index and handgrip strength in American adults: Data from National Health and Nutrition Examination Survey (NHANES, 2011-2014).
- Serum essential elements and muscle health in Chinese adults: a community-based study.
- [Survey of the dietary status and physical activity level and fitness of college freshmen in Chengdu].
- A comprehensive review of the physiology and evidence base to guide the use of ergogenic and medical supplements for enhanced cycling performance.