(Mike Stone/Reuters)

Anyone who’s ever experienced muscle cramps knows they’re no fun. They can be paralyzing. And in the case of Miami Heat star LeBron James, they can be painful not just physically, but also for the ego. (Gatorade’s comment was a little harsh.)

But they probably shouldn’t be. Muscle cramping is a legitimate medical problem, not an excuse. The Mayo Clinic writes:

“A muscle cramp is a sudden and involuntary contraction of one or more of your muscles. …Though generally harmless, muscle cramps can make it temporarily impossible to use the affected muscle.”

As to what causes muscle cramps, that’s tricky. Several factors can contribute, which are tough to diagnose or prevent and makes these episodes mostly unavoidable. Among the most common factors for athletes are overexertion in hot conditions. During Game 1 of the NBA Finals at San Antonio’s AT&T Center on Thursday, the air-conditioning went out, causing on-court temperatures to soar upwards of 90 degrees.

But why didn’t any of the other players also cramp up?

One factor might be dehydration, which James alluded was the problem. He told ESPN:

“I was losing a lot [of fluids] throughout the game. It was extremely hot in the building, you know, both teams, fans, everybody could feel it.”

Most medical authorities, including the Mayo Clinic, agree that lack of water can contribute to an athlete’s vulnerability to muscle cramps. However, a 2010 study published in “Medicine and Science in Sports & Exercise” argues otherwise. Competitor, a Web site dedicated to running, writes of the study:

“[R]esearchers at North Dakota State University used electrical stimulation to induce muscle cramps both before and after subjects cycled indoors in a hot environment until they were 3 percent dehydrated. The objective was simple: To see whether less electrical stimulation was required to induce cramping in the calf muscles when subjects were dehydrated than when they were hydrated. … [T]here was no difference in the amount of electrical stimulation required to induce cramping before and after dehydrating exercise.”

So if it wasn’t dehydration or simple fatigue, the what? Another common factor that can make some people more prone to cramps is a deficiency of potassium, magnesium or calcium, according to the Mayo Clinic. These mineral deficiencies can be treated with intravenous fluids, which James said he took during the game. He did not, however, elaborate what his IV cocktail consisted of. It could’ve been a simple solution of electrolytes to treat possible dehydration only.

Whatever it was, it didn’t work. James left the game with 7:31 remaining in the fourth quarter, when the muscle cramps in his left leg returned.

Going forward, James’s Thursday night cramps will likely not affect his play in Game 2, which is slated to take place in a hopefully cooler AT&T Center on Sunday. As any athlete who’s had a muscle cramp knows, the condition usually resolves itself, which is excellent news for the Heat, which needs a strong and healthy James to beat the Spurs. And James knows it. He told ESPN:

“It sucks not being out there for your team, especially at this point in the season.”