Photo credit: TriathlonMagazine.com

If the heat, humidity and scorching summer sun are making it tough to keep your cool when exercising outdoors, there’s no shame in taking it into the gym (just ask @RunEMZ!).

But don’t waste a workout; rather than running on autopilot, try tackling a new challenge with one of these 30-minute treadmill routines:

1. Take a hike. 

If you can’t hit the trails, mimic it indoors with a workout that combines brisk walking with various inclines to target your quads and butt.

Try this: 

• Walk at 3.5 miles per hour on a flat belt (zero incline).
• After the first minute, increase the incline by one percent every minute until it reaches five percent, and stay there for five minutes.
• Next, lower and raise the belt by five percent every two minutes until you’ve been exercising for 20 minutes.
• Spend the last 10 minutes repeating the first segment in reverse (starting at five percent incline for five minutes, gradually decreasing the incline by one percent for each of the last five minutes).

2. Roll with it. 

Once you’ve mastered walking at a small slant, it’s time to kick it up a notch and pretend you’re jogging on the rolling hills of San Francisco. Play with the speed, incline and duration to create a program that fits your needs, continually testing your limits to see greater gains in endurance.

Try this:

• Start slowly at five miles per hour and a one percent incline for the first three minutes.
• Bump up the speed to 6.5 mph for the next three minutes, but keep the incline the same.
• Then, slow down to 5.5 mph, raising the incline to three percent.
• Continue in three-minute intervals, pushing for higher speeds and slopes when your initial levels start to feel easy.

3. Play with speed. 

If sprinting in place for 30 minutes sounds like torture, try a few fun tricks to keep your mind occupied while you rack up the mileage. For example, if you’re watching a 30-minute TV program, try sprinting (80 percent of your all-out effort) during the commercials. Or if music is your motivation, make a special playlist and pick up the pace for every other song.

Try this: 

• Take a deck of cards and get creative by assigning a speed or incline by suit, color or number.
• Shuffle, and keep them in an envelope on the treadmill’s control panel.
• Every two or three minutes, draw a new card and do what the card says, which adds a nice element of surprise.

4. Tone your total body. 

A circuit workout is good for both calorie burning and short attention spans. Sure, it requires some coordination hopping on and off the treadmill to perform a series of exercises in between sprints, but there’s nothing like knocking out your cardio and strength training workouts at the same time.

Try this: 

• Warm up on the treadmill for five minutes at a light jog.
• Hop off, and do 15 push-ups and 15 lunges.
• Get back on the treadmill, jogging for one minute, sprinting for 30 seconds. Repeat this interval pattern three times.
• Hop off and do 15 bicep curls and 15 tricep dips. Repeat the treadmill segment.
• Get back off, hold a plank for one minute, and then do 15 shoulder presses. Repeat the treadmill segment.
• For your final strength segment, do 15 squats and 15 dumbbell rows.
• Hop on the treadmill one last time for a few minutes to cool down.