Lentils for people who train: what is in them and when to eat them

Lentils are one of the few foods that put decent protein and slow carbohydrates on the same plate, and they cost less than almost anything else in the kitchen. If you train three to five times a week, they can cover a solid share of your daily carbohydrate, iron and fibre needs. The catch is that most people eat them at the wrong moment and then decide lentils simply do not agree with them.

What is actually in lentils

Numbers for 100 g of dry lentils, which is roughly one and a half deciliters and the portion most people cook for themselves:

• about 340 to 350 kcal
• 24 to 26 g of protein
• 58 to 60 g of carbohydrates, of which 28 to 30 g is fibre
• about 1 g of fat
• 6.5 to 7.5 mg of iron, about 850 mg of potassium, about 120 mg of magnesium and about 3 mg of zinc
• about 400 to 480 mcg of folate

Lentils absorb water while cooking and roughly triple in weight. So 100 g of cooked lentils gives you about 115 kcal, 9 g of protein, 20 g of carbohydrates and 8 g of fibre. A 300 g plate of cooked lentils is about 350 kcal and 27 g of protein.

Lentil protein is good, but not complete

Lentils are high in lysine and low in methionine. In practice that means 25 g of lentil protein does not do the same job as 25 g from eggs or meat. Concretely, those 25 g contain roughly 1.8 g of leucine, while the target for a strong muscle building signal is 2.5 to 3 g of leucine per meal.

The fix is simple and costs nothing: add something richer in methionine to the same plate.

• 80 g dry lentils + 60 g dry rice: about 25 g of protein with a complete amino acid profile
• a plate of lentils + 200 g of yoghurt (about 7 g of protein and plenty of leucine)
• a plate of lentils + 2 eggs or 40 g of cheese
• a plate of lentils + 100 g of chicken or tuna if you are not eating plant based

When to eat them around training

Before training

With 3 to 4 hours before a session, eat the full portion and do not think about it. With 60 to 90 minutes to go, drop to 100 to 150 g of cooked lentils or take them as a blended soup, because 8 g of fibre per 100 g builds up in your stomach fast. A full 300 g plate 45 minutes before squats or a run is a reliable way to ruin a working set.

After training

This is where lentils shine, and there is no 30 minute window to chase. A meal of 80 g dry lentils + 60 to 80 g dry rice + an animal protein source or 200 g of yoghurt gives roughly 90 g of carbohydrates and 35 g of protein, which is plenty after a 60 to 75 minute strength session.

The day before a test or a competition

Cut the fibre. White rice or pasta is the better call, and lentils go back on the menu once you are not competing.

Iron and how to actually absorb it

Plant iron is absorbed poorly, often only 2 to 10 percent of what is on the plate. Two easy moves change that number:

• Add vitamin C to the meal. Half a raw bell pepper (about 70 mg) or the juice of half a lemon (about 20 mg) can double or triple absorption.
• Skip coffee and black tea for one hour before and one hour after the meal. Tannins can cut iron absorption by roughly half.

Bloating and how to reduce it

If lentils give you trouble, in most cases the culprit is the amount and how fast you introduced it, not the food itself.

What works in practice:

1. Start with 100 g of cooked lentils per meal and add 50 g each week over 3 to 4 weeks.
2. Soak brown and green lentils for 4 to 8 hours, throw out the soaking water and rinse. That removes part of the oligosaccharides and phytates.
3. Cook them all the way through. Undercooked lentils cause more trouble than overcooked ones.
4. Split red lentils are the easiest on the gut and need 10 to 15 minutes of cooking, while brown and green need 20 to 25 minutes, at roughly 1 part lentils to 2.5 parts water.
5. Cumin or fennel helps some people. Add acid such as lemon or tomato paste only in the last 5 minutes, since it slows the cooking down.

How much and how often

For most people who train, 3 to 4 servings a week of 80 to 100 g dry lentils is a realistic amount. In a fat loss phase they are useful because 300 g cooked keeps you full for about 350 kcal. In a gaining phase they are easy to load up, since one plate with rice and oil clears 500 to 600 kcal without effort.

When to see a doctor

• If you are constantly tired, get out of breath during easy sessions, or your heart rate spikes for no reason, get a full blood count and ferritin checked. Do not start iron supplements on a guess, excess iron is not harmless.
• If you have kidney disease or a restriction on potassium and protein, plan lentils with your doctor. A 300 g cooked plate carries around 1,100 mg of potassium.
• If bloating, cramps or diarrhoea last longer than 3 to 4 weeks, or you see blood in your stool or lose weight unintentionally, that is a medical appointment, not a diet adjustment.
• If you have diagnosed irritable bowel syndrome, work out your legume tolerance with a dietitian instead of guessing.

The short version

• 100 g of dry lentils gives about 345 kcal, 25 g of protein, 29 g of fibre and 7 mg of iron, and turns into roughly 250 to 300 g cooked.
• Lentil protein is incomplete, so pair it with rice, yoghurt, eggs, cheese or meat to reach 2.5 to 3 g of leucine.
• Eat the full portion 3 to 4 hours before training or after training, and cap it at 100 to 150 g cooked if you are 60 to 90 minutes out.
• Vitamin C with the meal raises iron absorption, coffee and tea within an hour on either side lower it.
• Bloating is handled by ramping up over 3 to 4 weeks, soaking, and cooking long enough.