We encounter lots of hurdles on the road to regular exercise: it seems like work, travel, home and family commitments always grab our attention and leave little time for anything else. Sometimes it’s just tough to imagine getting in the car and spending an hour or more at the gym.

But getting a little workout in every day is better than nothing, especially if you want to move the needle on your mood. One American Journal of Psychiatry study shows that just an hour of exercise a week can stave off symptoms of depression in some people; and a recent Journal of Happiness study revealed that 150-300 minutes of vigorous movement every week results in a significantly more positive outlook, with the most striking difference in those who were overweight. For a happy and healthy heart, adults should work out four to five times a week for maximum cardio benefits, say Texas researchers, as reported in the Journal of Physiology. Even exercising two to three times a week can make a difference in heart health, the study says.

Some tips to keep you motivated:

• Decide on how many minutes you can spare and block out that time on your calendar as early each day as possible. You’re more likely to keep up a morning habit than if you work out at night.
• Trust the process. In the beginning, you’ll hit patches of inertia and might wonder when the results will kick in, but as you keep going, your body will begin to crave exercise. It takes a full six weeks for major sculptural changes to start happening.
• Enlist a buddy. Whether it’s someone at home or a friend you can check in with, a little accountability goes a long way.
• Keep trying. One workout may not float your boat, but search for others that might. You’ll be smooth sailing in no time.

If you have seven to 10 minutes

The 7-Minute Workout, scientifically designed to maximize exercise benefits in a short amount of time, offers a suite of moves that you can do in a small space. There are many apps that offer variations on the basic workout, and you can also modify it to fit any particular limitations.

Grab a mat (and a cold glass of water for recovery) and fire up Mike Donavanick’s 10 Minute Insane HIIT (high intensity interval training) bodyweight boot camp workout on YouTube. The video leads you through butt-busting moves that get your blood going and your muscles screaming for mercy.

CorePower Yoga shows how much you can pack into a 10-minute, ab-strengthening flow class. Check out Popsugar Fitness to watch the video that promises to firm you up and calm you down.

If you have 12 to 15 minutes

The 12 Minute Athlete app has a universe of short workouts designed for different results, such as core conditioning or upper body. Some are centered on a variety of props like jump ropes or medicine balls; others rely on body weight alone.

Tabata, which originated in the 1970s for Japan’s Olympiads, involves doing a cardio exercise as intensely as possible, then taking a 20-second rest. This is the basis for many quick workout plans, including this 15-minute one from Shape magazine that involves free weights, thrusts, in-place sprints and push-ups.

Millionaire Hoy has a 15-minute workout that alternates 45 seconds of activity with 15 seconds of rest, to sculpt a six-pack, build strength and burn fat. He walks you through each step on YouTube, sweating right along with you.

If you have 30 minutes

Min Zhou of Get Fit with Mindy has a fun workout designed to be done in a hotel. In this video, she uses water bottles as weights but also suggests suitcases, resistance bands and free weights would work just as well.

Get a free peek at a Beachbody P90X workout with founder Tony Horton in this video class, which combines yoga moves, cardio and bodyweight resistance for a fun and sweaty good time.

Amy Kiser Schemper, a personal trainer and fitness instructor and the woman behind Body Fit by Amy, offers a 30-minute Pilates workout that’s like an express version of a mat class, no special equipment required. She combines traditional Pilates with strengthening moves, providing small rests and stretches in between.

Want something a little longer? Combine any of the above. And if nothing here quite fits the bill, know that it’s always beneficial to walk, run or bike for any period of time—even if you’re just going around the block.