Going to the gym regularly seems to be an exceptional act. Three 45-minute workouts are just a tick under the federal government’s recommendation of 150 weekly minutes of moderate activity. Yet according to the Centers for Disease Control and Prevention, more than three-quarters of United States adults don’t reach that threshold.

But let’s say you’ve established a fitness habit. The next challenge is what do with your time. Regardless of how solid your initial program is, eventually a sameness creeps in: the same exercises, same order, same weight — same routine overall. The body and mind respond by becoming bored. Is there a way to wake up your workout?

The easy antidote is to make a change. “In order to make something different happen, you need to challenge your body in a different way,” says Josie Gardiner, a personal trainer in the Boston area. You could hire a trainer to revamp your program. That isn’t a bad move, but it’s even simpler to slightly alter what you’re currently doing. Your time in the gym will be reinvigorated. And you’ll shift your mindset from just getting through your workout to believing, “I could do more than I thought,” Gardiner says.

Tweak your treadmill workout

By changing just one element, you can make your workout shorter — between 30 to 35 minutes — and more efficient. Choose among these options depending on how you feel.

Vary the speed. A fairly typical treadmill workout runs at a pace of 3.5 to 4 miles per hour for 45 minutes. Instead, interval train, Gardiner says. Research on healthy, young to middle-age adults shows that high-intensity interval training is better than endurance training at increasing VOmax, the amount of oxygen the body takes in and uses during exercise. A higher VO2max indicates better conditioning and aerobic performance. Warm up at your normal starting speed for five minutes. Then start your interval cycle by increasing your speed by 1.0 miles per hour for one minute, then returning to your base rate for two minutes. Repeat this cycle six to eight times, ending with a five-minute cool down at a slower pace. This workout takes less than 35 minutes to complete.

Vary rest time. As you build your endurance, try cutting the rest time in each interval cycle to one minute. This shortens your workout even more and makes it harder.

Vary the incline. Warm up at your starting pace for five minutes, then increase the slope of the incline by one degree every minute with a goal of getting to 10. Once there, come back down by one degree every minute. End with a five-minute cool down. This is another way of changing the intensity, and it only takes 30 minutes.

Tweak your weight workout

Choose just one element to change at a time:

Play with pace. When using weights, vary the pace at which you lift the weights up and bring them back down to starting position. Count 2 seconds up, 2 seconds down; 3 up, 1 down; 1 up, 3 down, 4 up, 4 down. Your muscles will work and react differently.

Add weight. If the last few reps of your set feels easy, you aren’t working hard enough — you have to strain a little. If that’s not happening, choose a heavier weight so that you find it difficult to do the last few reps. Aim for the fewest additional pounds that your gym options allow. Most importantly, maintain good technique. “The minute you lose form, you’ve lost the exercise,” Gardiner says.

Change your hand position. The modifications will hit different parts of the muscle. With bicep curls, rotate your hands towards each other, with thumbs on top instead of pointing towards the walls, to make the exercise into a hammer curl. With a lat pulldown, you can either narrow or widen your grip on the bar. With a seated row, you can use different bars; a triangular one for a close grip, the lat pulldown bar for a wide one. With lateral dumbbell raises, rather than lifting to the sides, lift the weights straight out in front of you to shoulder height.

Focus on the feel. Regardless of what you do when lifting weights, the fundamental aspect to remember is that you’re targeting a specific muscle. It sounds overly obvious and basic, but concentrate on the muscle and feel it squeeze. “It puts your brain in the middle of muscle,” Gardiner says. It strengthens the mind-body connection. What’s more, a small study of college-age men suggests that focusing on the contraction can increase muscle size.