Jessica Alba has an extensive workout routine—crossfit, bikram yoga, spinning, weight training, dance, and martial arts are some of the activities she does to keep fit. Still, there are times the 38-year-old actress, businesswoman and mother of three children is running low on time and needs a quick pick-me-up. On those days, Jessica performs a short, but very intense cardio session. In her social media, she revealed that the trick is to climb on the treadmill for 35 minutes.

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You can chooe to walk or run with zero incline, but the L.A.'s Finest actress opts for an inclination to cause less stress on her joints. She also divides this exercise routine into three phases that are completed in 35 minutes without stopping.

Part 1 (24 minutes)

Start running at high speed for two minutes. Immediately change the machine at medium speed and run for one full minute. Repeat eight more times, adding up to 24 minutes. To break a bigger sweat, set the treadmill to medium inclination, which will increase the pulse and burn more calories.

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Part II (6 minutes)

The second part to this exercise is shorter, but it's high interval. Run for 30 seconds at high speed then change to medium speed and lower the incline without setting the treadmill flat (to protect the knees). Afterwards, run for a minute at medium speed and with less inclination. Repeat the cycle four more times.

Part III (5 minutes)

Finally, run at a low speed with slight incline for the final five minutes. This cool down will return the pulse to its usual pace and will relax the muscles, avoiding tears and injuries.

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This routine is best to do ocassionally in order to compliment strength and toning exercises and to see results.

Happy working out!