
When you are starting a new diet and exercise program you may find yourself having leg cramps during the first few days or weeks of your new routine. To understand why you experience this and what you can do to prevent recurrence, we have to examine the cause of muscle spasms.
Most oftenly, leg cramps are caused by some combination of the following 5 reasons:
- Dehydration
- Electrolyte deficiency
- Low potassium, magnesium deficiency, calcium deficiency, and/or low sodium
- Vitamin deficiency
- Low thiamine (B1), pantothenic acid (B5), and pyridoxine (B6)
- Lack of muscle flexibility
- Overexertion
Let’s address each problem individually:
Dehydration
Drinking plenty of water (by plenty, we mean a gallon or more of water a day) is an important factor in keeping you feeling your best. Water is critical at the microcellular level in the Krebs Cycle to generate adenosine triphosphate (ATP), which your body uses to do pretty much everything. Ensuring that you meet your daily water intake goals will improve your energy level, as well as provide your muscles with the resources they need to function properly. Without adequate water intake, our muscles begin to accumulate waste byproducts, commonly referred to as “toxins”, that may cause spasms or cramping.
Electrolyte deficiency
Ingesting plenty of dark green, leafy vegetables will go a long way in keeping you out of trouble and cramp-free. Even if you are limited to low-carb foods, you can still find good sources of potassium, magnesium, calcium, and sodium. Frequently, the two main electrolytes of concern that are responsible for leg cramps are potassium and magnesium.
The National Institute of Health (NIH) recommend a dietary amount of at least 320 mg of magnesium for women and 420 mg of magnesium for men, and 4.7 grams (or 4700 mg) of potassium for both men and women. You could be experiencing muscle cramps due to a deficiency in these minerals and if so adjusting your diet could be all that you need.
The chart below illustrate how much certain food contain in potassium and magnesium. If you were to eat 8 oz chicken breast with 1 head of romaine lettuce and 1 cup of beets green for lunch (497 calories, 2581 mg potassium, and 192 mg magnesium), then eat 6 oz of 90% lean beef with 1 cup of spinach, 1 cup of broccoli, 1 cup of zucchini for dinner (437 calories, 3214 mg potassium, and 237 mg magnesium, you will then consume in a total of: 934 calories, 5795 mg potassium, and 429 mg magnesium, which will exceed your requirements for the two electrolytes.
Meat/Fish |
Potassium Content |
Magnesium Content |
8 oz chicken breast (230 calories) |
359 mg |
66 mg |
6 oz 90% lean beef (344 calories) |
618 mg |
40 mg |
6 oz salmon (354 calories) |
618 mg |
46 mg |
8 oz tilapia (292 calories) |
863 mg |
78 mg |
8 oz center cut pork chops (260 calories) |
960 mg |
46 mg |
8 oz cooked chicken liver (263 calories) |
526 mg |
23 mg |
Fruits & Vegetables |
Potassium Content |
Magnesium Content |
Romaine lettuce, 1 head (108 calories) |
1546 mg |
88 mg |
Beets green, cooked, 1 cup (30 calories) |
1309 mg |
38 mg |
Spinach, cooked, 1 cup (44 calories) |
839 mg |
157 mg |
Avocado, 1 cup (234 calories) |
708 mg |
42 mg |
Edamame (soy beans), 1 cup (189 calories) |
676 mg |
99 mg |
Zucchini, cooked, 1 cup (18 calories) |
325 mg |
21 mg |
Cauliflower, 1 cup (27 calories) |
320 mg |
16 mg |
Kale, cooked, 1 cup (69 calories) |
296 mg |
23 mg |
Tomato, 1 medium ( 22 calories) |
292 mg |
14 mg |
Broccoli, 1 cup (31 calories) |
288 mg |
19 mg |
Strawberries, 1 cup (47 calories) |
220 mg |
19 mg |
If you feel that you are unable to ingest the required amount of vegetables and have leg cramps that won’t go away, you may benefit from short-term supplementation with a daily magnesium and potassium tablets.
Vitamin Deficiency
Deficiencies in Vitamins B1, B5, and/or B6 may be causing you cramps. The mechanism behind this is not currently well understood, however evidence suggests that supplementing these vitamins may help treat and avoid cramps.
Thiamin (Vitamin B1) is necessary for the proper functioning of the muscles, nervous system and heart. Thiamin deficiency has been known to cause insomnia, fatigue, depression, constipation, irritability, heart problems and stomach problems. Thiamin is abundant in organ meats, soybeans, egg yolks, poultry, broccoli, and asparagus. The recommended intake is 1.5 mg of Vitamin B1 daily.
Pantothenic acid (Vitamin B5) is responsible for the production of coenzyme A that is associated with the metabolism of fats and carbohydrates as energy sources. Pantothenic acid is found in organ meats, egg yolk, and broccoli, fish, shellfish, chicken, milk, yogurt, mushrooms, and avocado. Deficiencies are rare, but pantothenic acid deficiency may result in fatigue, insomnia, depression, irritability, vomiting, abdominal and leg muscle cramps. The recommended intake is 3-7 mg of Vitamin B5 daily.
Pyridoxine (Vitamin B6) assists in the degradation and production of amino acids and in the process that converts amino acids into fats or carbohydrates. Vitamin B6 is involved in fat/carbohydrate metabolism, the removal of fluids during premenstruation, and healthy skin. It can reduce symptoms of hand numbness, leg cramps, muscle spasms. Deficiencies have been known to cause anemia, dermatitis, hair loss, anxiety, leg cramps, water retention, anemia. The recommended intake is 1.3 to 1.7 mg of Vitamin B6 daily.
Lack of muscle flexibility
Exercise consisting of particularly intense physical activity can cause your muscles to fatigue, become sore, and spasm. Take every effort to stretch the muscle to cool down shortly after you exercise, and make an effort to incorporate stretching into your routine wherever limitations appear. Post exercise stretching of the muscles helps the fibers relax, reset, and promotes good circulation for recovery after exercise.

Overexertion
Your body needs adequate rest after a difficult workout. Any time you put yourself through high stress episodes such as exercise, you will need time to recover so you can improve your performance for next time and give your body time to catch up with all the good you’ve done. If the muscles are overworked and tired, you may get painful spasms that can in turn hinder your ability to stick with your gym routine.
Unfortunately as with any drastic lifestyle change, there will be unwanted side effects accompanying your new diet and exercise routines. However with a little planning and preparation you should be able to prevent muscle cramps from negatively impacting your progress. So eat right, rest well, exercise smart, and stay hydrated and keep up the good work.