Browse evidence-based analysis of health-related claims and assertions
Log in to see full claim details, scientific mechanisms, and cited studies.
Drinking beetroot juice with 400 mg of nitrate raises levels of nitrate and nitrite in the blood of young, active men during leg exercise, but does not improve how well they perform, how much blood...
In men who regularly lift weights, taking L-citrulline and citrulline malate leads to similar improvements in upper body endurance and nitric oxide metabolite levels after exercise, meaning adding...
Taking L-citrulline or citrulline malate supplements does not lower the levels of lactate or urea in the blood after resistance exercise in men who regularly train with weights.
In men who regularly lift weights, taking L-citrulline or citrulline malate supplements for six weeks does not lead to greater increases in maximum strength compared to not taking them, even though...
Taking L-citrulline or citrulline malate regularly may raise levels of nitric oxide metabolites after exercise in men who train with weights, and both forms appear to have comparable effects.
Taking 8 grams of L-citrulline or 12 grams of L-citrulline DL-malate daily for six weeks may help resistance-trained men perform more repetitions to failure in bench press and incline press exercises...
Taking 10 grams of L-citrulline daily for four weeks lowers aortic systolic blood pressure by 4 mmHg in postmenopausal women with hypertension, without altering aortic stiffness, suggesting a direct...
In hypertensive postmenopausal women, increases in blood flow to the forearm during hand exercise after taking L-citrulline are linked to improved dilation of the brachial artery, suggesting that the...
Taking 10 grams of L-citrulline daily for four weeks leads to a small increase in oxygen levels and a decrease in deoxygenated hemoglobin in the forearm muscles of hypertensive postmenopausal women...
Taking 10 grams of L-citrulline daily for four weeks increases blood flow and vessel dilation in the forearms of hypertensive postmenopausal women during handgrip exercise.
Taking 10 grams of L-citrulline daily for four weeks leads to a measurable improvement in blood vessel function and a small reduction in blood pressure in women with high blood pressure who have gone...
Taking caffeine before high-intensity sprint workouts does not lead to greater improvements in blood fat levels—such as cholesterol and triglycerides—than doing the workouts without caffeine, in...
In overweight and obese women, 12 weeks of sprint interval training reduces fat mass and improves strength, heart and lung fitness, and metabolic health. Adding caffeine to this training provides...
Taking caffeine before high-intensity interval workouts may lead to more consistent changes in body fat, muscle strength, heart fitness, blood sugar, and fat-related hormones among overweight and...
In overweight and obese women, taking 3 mg/kg of caffeine before sprint interval training for 12 weeks leads to larger decreases in fasting blood glucose and more favorable changes in certain...
In sedentary overweight and obese women, taking a caffeine dose of 3 mg per kilogram of body weight 60 minutes before three weekly sprint training sessions for 12 weeks is associated with larger...
Taking caffeine while doing resistance training does not lead to meaningful changes in body fat or muscle mass over six weeks in active men, even though some muscles may appear thicker.
In recreationally active men, caffeine may help increase muscle thickness slightly during the first 6 weeks of strength training, but it does not lead to greater muscle growth or improved performance...
Taking caffeine supplements during upper-body weight training may lead to greater increases in the size of the biceps and triceps muscles compared to other muscles, without changing overall body...
Taking caffeine supplements for six weeks while doing strength training does not lead to measurable improvements in maximum strength, endurance, or body fat and muscle mass in men who exercise...
In recreationally active men, taking a specific dose of caffeine before upper-body workouts three times a week for six weeks is linked to a larger increase in biceps muscle thickness compared to a...
In young men who rarely consume caffeine, performance on a one-rep max bench press test improves even when they take a sugar pill instead of caffeine, suggesting that expectations or psychological...
In young males, whether someone is regularly strength-trained or just casually active does not change how much acute caffeine improves muscular endurance, jump height, or one-rep max strength.
Taking a dose of 6 mg of caffeine per kilogram of body weight has almost no meaningful impact on how much weight a young man who rarely consumes caffeine can lift in a single repetition of bench...