A muscle cramp is a sudden and involuntary contraction of one or more of your muscles. If you've ever been awakened in the night or stopped in your tracks by a sudden charley horse, you know that muscle cramps can cause excruciating pain. Though generally harmless, muscle cramps can make it temporarily impossible to use the affected muscle.
Long periods of exercise or physical labor, particularly in hot weather, may lead to muscle cramps.
Causes--Overuse of a muscle, dehydration, muscle strain or simply holding a position for a prolonged period of time may result in a muscle cramp. In many cases, however, the exact cause of a muscle cramp isn't known.
Although most muscle cramps are harmless, some may be related to an underlying medical condition, such as:
·         Inadequate blood supply. Narrowing of the arteries that deliver blood to your legs (arteriosclerosis of the extremities) can produce cramp-like pain in your legs and feet while you're exercising. These cramps usually go away soon after you stop exercising.
·         Nerve compression. Compression of nerves in your spine (lumbar stenosis) also can produce cramp-like pain in your legs. The pain usually worsens the longer you walk. Walking in a slightly flexed position — such as you would employ when pushing a shopping cart ahead of you — may improve or delay the onset of your symptoms.
·         Mineral depletion. Too little potassium, calcium or magnesium in your diet can contribute to leg cramps. Diuretics — medications often prescribed for high blood pressure — may also deplete these minerals
Symptoms- Most muscle cramps develop in the leg muscles, particularly the muscles in the calf. In addition to the sudden, sharp pain, you may also be able to feel or see a hard lump of muscle tissue beneath your skin.
CUPRUM METALLICUM 12—An excellent remedy for cramps. It is useful in cramps of calves, feet or legs, soles, palms, fingers and toes. The cramps start with excessive weather and high temperature. . This remedy is popular in sports athletes
MAGNESIUM PHOS 6X, 1M –Another top remedy for muscle cramps. Writer’s and Player’s cramps in the wrists, hands, and figers due to excessive and long writing or use of fingers and hands. Numbness is usually present and there is relief by pressing the affected part, by warmth and massage
ARNICA MONTANA 30- Cramps as a result of overexertion or from muscular fatigue. Limbs feel as if beaten. Cramps are better  on starting to move and worse from prolonged movement , heat and light pressure
RHUS TOXICODENDRON 30- Cramps  by swimming in cold water. Cramps in calf muscles and legs by stretching , specially at night. Cramps , worse rest and better by movement.
PLUMPUM METALLICUM  200—Cramps in calves and toes at night in bed