01 · When supplements helpWhen supplements make sense
A good basic diet — with sufficient carbohydrates, proteins, healthy fats, and micronutrients — always remains step one. Supplements are not a replacement for real food, but can provide strategic support when your body requires more than you get from food every day. Think of heavy training weeks, higher volume toward a competition, periods with little sunlight, or moments when recovery requires extra attention.
For runners it is not about “taking more,” but about targeted supplementing what you lack. The biggest gains usually come from simple basics: vitamin D in the winter, magnesium if you have a deficiency, electrolytes during prolonged exercise or heavy sweating, and caffeine during races. Everything beyond that only makes sense if it fits your goals and load — and if your diet is already properly organized.
First, make sure your recovery meals are in order. Recovery Nutrition: Best Post-Workout Snacks and Drinks provides practical examples of complete recovery options that provide the foundation before reaching for supplements.
02 · Gels and sports drinksGels / sports drinks while running
Gels and sports drinks aren't just for marathon runners — they're an instant source of quickly absorbed energy. During intensive exercise, your body is highly dependent on carbohydrates. As soon as your glycogen stores start to decline, you will notice this in your legs feeling heavy, a decreasing pace, and an increasing heart rate. By feeding on time, you prevent that “blow” and you can maintain your pace for longer.
During races (5K, 10K, half marathon, marathon, or a personal record), gels are the most efficient way to reach your carbs per hour. Most sports gels contain 20–30 grams of carbohydrates, and many sports drinks 30–60 grams per liter. For optimal performance, aim for 30–60 grams of carbohydrates per hour on runs longer than 75–90 minutes. Under an hour, it's usually not needed; in between, it depends on your pace.
Do you use gels? Always test them during training: taste, texture, and stomach tolerance differ enormously per brand. Combine gels with water and adjust your food timing to your pace and point in the race.
03Commonly used supplements
Magnesium
Protein
Vitamin D
Nitrates (beet juice)
Not every supplement has the same benefit, but some can provide clear added value for runners — if chosen well and dosed correctly. Below you will find the most commonly used options with a brief explanation when they make sense.
Magnesium
Magnesium plays a role in muscle contraction, nerve conduction, and relaxation. There's no proof that a supplement reduces cramps, stiff calves, or restless legs: in older adults with ordinary muscle cramps it probably doesn't help, and there's too little good research on cramps while running. So it's not a cramp remedy, but it can be useful if:
your diet doesn't give you enough magnesium, or your doctor or sports dietitian finds a deficiency.
Dosage: 200–250 mg in the evening, preferably magnesium bisglycinate or magnesium citrate (good absorption, less chance of intestinal complaints). In addition, make sure your fluid and salt balance is correct. To learn how to estimate your fluid loss, read Hydration during hot runs.
Protein
Proteins provide amino acids that your body uses to repair muscle fibers and support the immune system. A shake is especially useful when you:
don't have time for a full meal, or are on the road immediately after your training.
Dosage: 20–25 g protein with your next meal or within a few hours after exercise (whey or vegetable such as pea/rice). A shake does not replace a meal, but is perfect for the first recovery moment.
Vitamin D
Vitamin D supports bone health, muscle function, resistance, and hormonal balance. Runners who see little sun, work office hours, or train in the winter months often have low values.
Dosage: 1000–2000 IU per day is a usual safe amount for low blood values. If possible, have your blood values measured for personal advice. Optionally combine with vitamin K2 for better absorption and bone health.
Nitrates (beet juice)
Nitrate supplements, such as concentrated beet juice, can reduce the oxygen cost of exercise. That means you need less oxygen at the same pace — a subtle but effective advantage in competition. Mainly works for:
tempo running, long intervals, and races from 5K through the half marathon.
Dosage: 400–600 mg nitrate (usually 1 shot of beet juice) 2–3 hours before exercise. Please note: always test beet juice in advance due to... stomach reaction.
Use nitrates specifically around speed training. Improving running speed: 6 proven methods gives examples of sessions where beet juice provides extra value.
04 · Supplement comparisonComparison of supplements for runners
Supplements can support your training, but only if your basic nutrition, sleep, and recovery are already in order. They do not replace good meals, but can provide that extra support during tough training weeks, hot conditions, or competition preparations. This table helps you see at a glance which supplements are actually relevant for runners — and when to use them.
| Supplement | Target | When to use | Dosage |
|---|---|---|---|
| Magnesium | Supports muscle function; no proven effect on cramps | If you have a deficiency or low intake, for example in the evening | 200–250 mg (bisglycinate/citrate) |
| Protein | Supports muscle recovery | Within a few hours after your workout, especially if you will not eat soon | 20–25 g protein (shake or snack) |
| Vitamin D | Important for bone health, muscle function, and resistance | Daily in autumn/winter or with little sunlight | 1000–2000 IU per day |
| Nitrates (beet juice) | Reduce oxygen costs, improve endurance | 2–3 hours before races or hard tempo/interval sessions | 400–600 mg nitrate (1 concentrated shot) |
05 · Use guidelinesGuidelines for wise use
Supplements can be valuable, but only if you use them thoughtfully and purposefully. Many runners take too much, too often, or without knowing what their body really needs — resulting in waste or even side effects. By following a few simple guidelines, you will get the benefits of supplements without the pitfalls.
Supplements supplement nutrition, never replace meals. Keep a log of intake and effects (energy, recovery, digestion). Choose certified products (such as Informed Sport) to avoid contamination. Always consult with a sports dietitian or doctor if you have any medical conditions or medication use.
Don't forget that sleep and recovery remain the foundation. Sleep and Recovery: Impact on Your Performance shows how rest can reduce your need for supplements.
06 · Do you need supplements?Checklist: do you need a supplement?
Supplements seem attractive, but not every runner needs them — and certainly not always. A good decision starts with self-evaluation: what do you eat, how do you train, and what are you trying to solve? This checklist will help you make more conscious choices and prevent unnecessary or incorrect supplementation. Think of it as a short reality check before you buy something.
Before you start, ask yourself these five questions:
07 · MistakesCommon mistakes
Supplements can be useful, but only if you use them in a targeted and thoughtful manner. Many runners jump into them too quickly, rely on marketing claims, or use them at times when nutrition or recovery is actually the real problem. By avoiding these common mistakes, you can benefit from supplements — without the risks or disappointments.
Blindly taking supplements. Without knowing whether you have deficiencies. Consider taking magnesium or vitamin D “just to be sure.” This may be unnecessary or even cause complaints. If in doubt, have values checked.
Taking too high doses. In the hope of seeing results faster. More is rarely better: high doses of magnesium can cause gastrointestinal complaints and too much vitamin D can be harmful to kidneys and blood values.
Expect supplements to replace performance. Training, nutrition, and recovery always remain the basis. A recovery shake only works if you also have your sleep, rest weeks, and nutrition in order.
No consistent use. The effect of many supplements (such as vitamin D or magnesium) builds up gradually. Taking it occasionally is of little use — you only notice anything after weeks of consistent use.
