Spoiler: If you've been doing the same thing for years, it's probably time.
Getty Images

You go to the gym at the same time each day, do the same cardio and strength routine or take the same class, wear the same type of work out clothes, and wind down the exact same way every time. Does this sound familiar? If so, listen up: It's time for a change.

Every day, our lives are scheduled. We get up at a certain time, go to work at a certain time, eat at a certain time, and if possible work out at a certain time. Your workout should be your daily escape, not something you do like a machine just going through the motions. For the best results, you should be switching up your fitness routine all the time. For some this may be every day, for others every three days, and still others every three weeks.

To figure out when and how is exactly right for you to change your routine, here are a few guidelines.

When to Change Your Exercise Routine

1. Your body isn't changing. If you train the same way day in and day out, you will not experience continuous growth. The human body adapts quickly to exercise stimuli, and once it adapts it needs change. To put it simply, think about people who drink coffee, tea, or energy drinks to kickstart their day. They may start off with one cup or can. But as time progresses, their bodies adapt to this stimulant and more is required for the same effect. This is exactly how exercise works. Let's say you start taking a dance class, a cardio class, or a weight training or movement program. Eventually your body will adapt to the stimuli and need more change to grow.

2. You're bored. Send your body on a first-class vacation to a place that has never been before. If you're an elliptical queen, jump into a cardio dance class. Pilates people, try weight training. And if you work out alone, ask a colleague or loved one to join you. It's hard to stay committed to anything that you are not excited about. (Related:The Best Workout for Your Body Type)

3. You get injured. If your workout leaves you sore and tired, that may be a good thing, as long as it's not too much. Performing a workout should make you energized and lift your emotions. Yes you may feel sore and tired the next day, but a continuous feeling of being tired and not able to recover from a workout may be a sign of overtraining, which can lead to burnout or, worse, injury. To avoid overtraining, implement a recovery period of three to seven days of workout rest every eight to 10 weeks.

How to Change Your Exercise Routine

1. Make a slow transition. If you have been training in one linear fashion, say on a treadmill or elliptical four days a week, don't jump into a intense multi-dimensional cardio class and attempt to keep up with the instructor. Start slow. When you head into the new class, let the instructor know your background or discuss the best class for you with the facility's group exercise instructor.

2. Ask for help. When you're switching to a new workout entirely, make sure you know how to do it correctly. For example, if you've never lifted a weight and are thinking of incorporating strength into your routine, consult the fitness manager and ask for a free training session to learn proper technique. (Related: The Top 50 Hottest Trainers in America)

3. Change your intensity. If you feel that your workout has become less of a challenge, gradually increase the intensity. So if you are taking 60 seconds between each set, drop your recovery to 45 or 30 seconds. Another way to increase intensity: If you have an hour, set up 20-minute fitness challenges and work without taking a rest, or see how many repetitions you can achieve of your favorite exercises. Remember to always practice good form.

4. Add a partner to your mix. Having your besty sweat it out with you will naturally push you harder. Plus he or she may have be able to introduce you to a new style of training, workouts, or exercises, and may make it a lot more fun.