A fitness plateau can be your body's signal that it's time for a change, experts say, or a sign that you've been looking for progress in all the wrong places.

"A plateau is a period where you stop making progress," said Marshall Roy, a New York City-based personal trainer at Equinox, the national chain of fitness centers. "It isn't a death sentence and it's not necessarily a bad thing. It's feedback from your body that what you're doing has stopped working."

The human body will adapt to become as strong or lean or resilient as you train it to be, Roy explained. So if you keep giving it exactly the same challenge it will not progress.

"Say you're a woman who wants to lose body fat. You've been doing Pilates for a couple of months and experiencing the results you want. Then you stop seeing it," he said. "It may be time to try strength training or swimming."

Roy believes best way to avoid plateaus is to have a long- term, progressive, goal-oriented plan. He said people are generally too quick to abandon a solid routine to follow the latest craze or celebrity endorsement.

"We call it training A.D.D. (for Attention Deficit Disorder)," he said. "They hop around different styles. It doesn't work. How would you know if you're making progress if you're always changing? Consistency is how you track your progress."

Roy suggests giving a workout at least eight, and preferably 16, weeks to allow the body to adapt to it.

He also notes that in fitness, as in nature, everything happens in cycles.

"There is a time for progress and a time for recovery and maintenance," he said. "If my client is an accountant, I'm not going to plan a brutal workout (at tax time) in April. Summer is a great time for a teacher to make strides."

Sometimes, he said, the problem lies outside the gym.

"Ask yourself: have I changed my diet? Do my workouts lack vigor? Has my stress level increased?" he said. "Try to isolate the variable that led you to stall. Most of the time it's a lifestyle factor that's the reason."

Shirley Archer, a fitness expert and spokesperson with the American Council on Exercise, said whether you're doing aerobics, strength or flexibility training, fitness plateaus, while no fun, are inevitable if you always repeat the same workout.

"SAID (Specific Adaptation to Imposed Demand) is a tried and true training principle," she said of the tenet that the body will adapt to the specific demands placed upon it. "It guides our training."

Our bodies adapt to what we do and become more efficient over time, Archer explained, expending less energy to perform the same activities.

"Studies show that in as few as six workouts, our neuromuscular system has adjusted to a particular stimulus," she said. "In other words, we're no longer surprised and accept that activity as part of the new normal."

Add variety, said Archer, who went on to quote what she calls her best rule of thumb: "If your mind is bored, your body is bored too. Mix it up."

(Editing by Patricia Reaney)

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