Signing up for your first endurance race, whether it’s a 10K or your first marathon, is a big decision. After all, you’re about to give up happy hours, sleeping in, and boozy brunches for this event. So why would you give it as much consideration as swiping left or right on your next potential Tinder match?

The answer: You don’t. The first step is, of course, finding the right training plan. Whether it’s 10 weeks, two months, or longer, a set schedule helps you run, bike, or swim your heart out on race day without worrying if you’re actually prepared.

However, no one-size-fits-all training plan exists, says Jordan Metzl, M.D., a sports medicine physician and author of Running Strong. “Following a training plan built for the masses or simply doing what everyone else does when you’re training with a group is rarely the best way to go.” That can lead to injury, which Metzl estimates he sees in 40 percent of first-time marathoners in his practice.

Pick the Right Plan

Randomly picking a plan may set you up to fail (or get injured). Instead, use these tips to find one that works for your body, schedule, and goals.

  • Choose a plan that aligns with your fitness level. That means no expert-level plans if you’ve only ever run a 5K, says Jess Underhill, a certified run coach and owner of Race Pace Wellness.
  • Make sure it fits into your schedule. For example, if you only have time to run three days per week, don’t choose a plan that schedules five morning runs per week (even if it’s beginner-level), Underhill says.
  • Mix it up. A smart plan includes at least one strength training session, cross-training, and one to three rest days per week, Underhill says. If you get injured easily, try to find a plan that has flexibility for less running and includes low-impact options for cross-training days. And if you know you need to work on getting stronger, choose a plan that includes at least two days of strength training.
  • Check out who created the plan. Underhill recommends looking for qualifications like a degree in an exercise-related field like exercise physiology or kinesiology, or a personal training certification. The plan’s creator should also have experience working with endurance athletes.
  • Be aware of “get fit fast“ programs. “The plan should build up conservatively,” Underhill says. A typical marathon training plan lasts 16 to 20 weeks, while half-marathon plans are 10 to 12 weeks in length. “Shorter training plans (eight weeks or less) can put you at risk for injury, no matter your fitness level,” she says.
  • Do your homework. Google the training plan to look for positive reviews and how many people have used it, or talk to friends who have reached their own goals with a particular plan, suggests Jeff Galloway, a running coach and former U.S. Olympic runner.
  • Scale up gradually. Galloway’s marathon training plans employ a run-walk-run method, designed to boost success rates while limiting injuries. Metzl also offers a series of scalable marathon training plans in his book, Running Strong. Or check out programs and advice backed by credible publications like Runner’s World and Triathlete Magazine.

Bounce Back from Roadblocks

Let’s say training starts off well, but suddenly you miss a cross-training session, or that one rest day turns into two. Inevitably, you’ll face some setbacks, whether it’s illness, injuries, family issues, or a big project at work. “I haven’t had a client yet that hasn’t had some interruption during training season,” Galloway says.

While it’s important to stick as close to the schedule as possible, you don’t have to bow out completely if you miss a workout or two. Here’s what Underhill has to say about getting back on track—stat.

My shins have been bothering me during half-marathon training, so I took off a few days and cut down on mileage.

Say you only work up to nine miles. Should you bow out of the race, or should you be able to run the 13.1? First, see a qualified healthcare provider such as physical therapist or an orthopedic physician to rule out any serious injuries. Once cleared by a professional, you could still run a half-marathon even if your longest run was only nine miles—but only if that run wasn’t more than three weeks before the race. If the doctor says you shouldn’t run, then you should follow that advice and bow out. You can work on healing your injury and set your sights on a different race at a later date.

I pulled a hamstring. Do I take time off or cancel my race plans?

The exact diagnosis of a “pulled” hamstring should come from a physician or a specialist like a physical therapist. In these cases, the doctor or therapist should advise whether time off is required or if other training modalities (i.e., water jogging) are recommended. Prior to seeing a doctor or specialist, rest is advised.

I felt hungover on Sunday morning and missed my long run. Can I make it up with a couple of smaller sessions throughout the week?

No. The physiological training adaptations and mental stamina gained from long runs are what enables the body and mind to be able to run long distances. While short runs contribute to your overall fitness, they will not make up for missing a long one.

I had a bad cold and missed a week’s worth of training. Should I return to my scheduled routine once I feel better?

No. Not only did you miss a week’s worth of training, but your body utilized a lot of energy to recover. As a result, your body is likely in a weakened state. Try one easy week of training (low intensity/low mileage) before reverting back to the planned schedule.

I had a serious illness. Do I need to quit training completely?

While this decision is largely based on what a doctor or specialist advises, illness with a high temperature, fractures, or severe muscle and connective tissue injuries that result in pain will likely result in pulling out of a race. However, depending on the injury or illness, a doctor or specialist may recommend other training modalities. Consult an expert.

I had to work several late nights and missed a training run as well as a strength workout.

In this case, double up on workouts on the next rest day. You can get by with a shorter version of both workouts to save some time.

I had a bad run early on in the plan. Should I just give up?

Don’t stress. “People go out and run harder or longer than they should, and they have a bad experience,” Galloway explains. “If they can’t make it through a three-miler, they wonder, ‘How the heck can I run a half marathon?’” But don’t self-sabotage. With the right strategy, almost anybody can finish a half- or full marathon, Galloway insists.

I’m exhausted but need to get in a long run before a weekend away. Do I wake up and run or stay in and rest?

Give it a try. As noted previously, adhering to the set training schedule is important. While there are times when rest is advised, in this case it would be best to do the run, but perhaps reduce the mileage and intensity. Often, once warmed up, your body and mind will start to feel much better and you end up having a great run.

I went out for a long run on Sunday but only had time to do about half the distance I intended to do. On Monday (a scheduled rest day), should I attempt the long run again?

Nope—rest. Adhering to the schedule is of critical importance when training. Additionally, whether due to overtraining, mental stress, or just having an “off day,” your body needs rest—regardless of the exact reason for your fatigue.

I really want to go out for a friend’s birthday Friday night, but I have a long run scheduled on Saturday.

Pick one weekend night to go out, but not both. Many people choose to stay in Friday night, then do their long run or workout on Saturday morning so they can go out on that evening without worrying about staying out too late. In this case, switch your night out. Then, during the week, set a curfew and a drink limit. By doing so, you’ll have a plan in place that can help you stay social without ruining your training.

The Takeaway

While it’s important to be dedicated to your training plan, sh!t happens. “Life goes on even when we’re training for a race, and missed workouts from time to time are normal,” Underhill says. “However, if you miss weeks of training, you’ll need to adjust your goal, drop down to a shorter race distance, or maybe even pick a race at a later date.” But as long as you follow the tips above and stay nearly on schedule, feel confident and secure that you can do it!