You’ve resolved to start an exercise program, and this time you mean it. Sure, you’ve made the promise to yourself before, but life got in the way — the busy job, the family obligations — and then before you knew it, you hadn’t done anything in so long that it became easier to keep doing nothing. Well, no more excuses. This time, you’re determined to jump back into a routine, and nothing is going to knock you off course.

Then, before you’ve even had your first weigh-in, you’re sidelined.

“People who are unaccustomed to exercise are especially prone to getting hurt — whether from a lack of fitness that puts them at risk of a muscle, tendon or other soft tissue injury, or from a lack of familiarity or competence with the sport and the equipment that goes with it,” says Daniel V. Vigil, an associate clinical professor in the departments of family medicine and orthopaedic surgery at the David Geffen School of Medicine at UCLA and associate team physician in the UCLA Department of Intercollegiate Athletics.

If you’re coming out of your winter hibernation eager to shed those extra pounds through a fitness routine, that’s fine. But Vigil would remind you that many people enthusiastically embark on an exercise program, only to be derailed because they didn’t take certain basic precautions. He recommends the following strategies for staying active and injury-free.

Start Small

Driven by enthusiasm — and maybe some wishful thinking — many people set lofty goals and are too eager to get there. They remember what they used to do, failing to realize (or admit) that they’ve gotten older, or that it’s been a while. “One of the most common mistakes people make is to overestimate their level of fitness,” says Vigil. In sports medicine it’s known as the rule of “toos” — the tendency among many casual athletes to go too hard for too long, too soon. Vigil’s advice when you’re getting started is to take a test run — a 5- or 10-minute jog around the block, a brisk walk, a quick ride on the bike, a short swim — to see how you feel. You should be at a level at which you’re exerting yourself but can still speak in full sentences with your exercise partner. Make a second assessment the next day. If your muscles ache or that old arthritic knee is acting up, you’ve likely done too much.

Dress for Success

Blisters, painful toenails and the heel pain known as plantar fasciitis are just a few of the reasons that dusting off that 5-year-old pair of running shoes at the launch of your exercise program is probably a bad idea. Whether it’s finding a comfortable bicycle helmet to protect against head injury, choosing clothing that prevents chafing, or paying attention to the grip of your racket to prevent tennis elbow, proper equipment is critical not just for enhancing athletic performance, but also for keeping you in the game.

Stay True to Form

The mechanics of your swim stroke, the form of your serve, the fit of your bike … if you’re not doing it right, you are also putting yourself at risk. Vigil recommends seeking out a mentor when getting started to ensure proper equipment and technique. “You don’t need to spend a lot of money on some fancy coach,” he says, “but find a friend with some experience who can provide guidance on an activity you might not be as familiar with.”

Walk Before You Run

Vigil notes that the benefits of warming up, both for injury prevention and enjoyment of the exercise, are indisputable. Rather than jumping right into an activity, take a couple of minutes to gradually get your muscles accustomed to the movements you plan. “Injuries often stem from the repetitive motion,” Vigil explains. “The warm-up reminds the body what it’s like to do those things. It begins the dilation of the blood vessels to the muscles so that there is blood flow and oxygen going to them by the time you’re ready to begin sustained activity.”

Mix It Up

To lower the risk of so-called overuse injuries — tendinitis, stress fractures and other types of damage resulting from cumulative trauma to the same muscle or joint — it’s also important to cross-train, devoting at least one day a week to exercising parts of the body that might have been neglected during your go-to activity. “It behooves us all to take a break from the repetition of our chosen passion, both for overall fitness and to reduce injury risk,” Vigil says.

Read the Signs

In many cases, your body will offer early warning cries when an injury is near, and it pays to listen. “If you’re starting to develop localized pain, it’s a signal you might be overdoing it,” Vigil says. “If you ignore it, you are setting yourself up for a true injury.” We’ve all heard the “no pain/no gain” mantra, but that doesn’t necessarily apply to the casual athlete. Moreover, Vigil explains, there’s a difference between general fatigue — a positive sign that you’ve pushed yourself to your fitness limit — and experiencing a muscle twinge every time your left foot hits the ground. The latter is a suggestion that you have a weak link in the chain, and it’s smart to give yourself a couple of days to recover while the problem is still easily reversible.

Eat, Drink and Be Healthy

The wisdom in listening to your body also applies to food and drink. Stay hydrated, but don’t overdo it: Not long ago, conventional wisdom said to consume lots of water before and during physical activity, but doctors now advise drinking only when thirsty. Your body is also bound to speak up if you push it a half-hour after consuming a Big Mac; instead, Vigil recommends timing exercise so that it’s several hours after you’ve eaten. The post-workout meal — including a carbohydrate, some protein and a healthy fat — is then crucial to the fitness-building regimen by facilitating recovery.

A Marathon, Not a Sprint

It’s easy to view the looming threat of injury as just a potential nuisance. But the reality is that too often, an injury can set us on a sedentary spiral. “The goal is to establish exercise as part of an every day, every week, rest-of-your-life activity,” Vigil says. “In order for that to happen, the activity has to be enjoyable and something that can reasonably be done within a busy lifestyle. But it also has to be injury-free. If you wind up hurting yourself, it’s going to be hard to stay with it.”