The What, When, & How’s of Cardio

There’s a “c-word” in fitness, and no it’s not the one you’re thinking of! Get your minds out of the gutter. The word I’m talking about is… cardio! I LOVE cardio. Running, sprinting, biking, dancing, stair climbing, you name it. I live for the adrenaline I get from pushing myself to run faster, bike harder, or dance bigger. However, for many of you, cardio is like the opposite sex. You can’t live with it or without it. You know it’s good for you and helps you burn fat but you just dread it. This love-hate relationship is totally normal. Cardio can be extremely boring and time consuming… if you’re doing it wrong! Today is the day your cardio gets a makeover. I’m going to tell you the what, when, and how’s of cardio to decrease the amount of time spent and increase results! I’m like a fairy godmother, right?!

The What, When, and How's of Cardio

So WHAT exactly is cardio?

According to the American College of Sports Medicine, cardio, or cardiovascular exercise, is any activity that increases heart rate and respiration while using large muscle groups repetitively and rhythmically. There are lots of different types of cardiovascular exercise including running, biking, swimming, dancing, playing sports, attending an aerobics class, etc. There is no “right” type of cardio. Find the modes that you enjoy most and then switch it up a few times a month.

WHEN is the best time to do cardio?

Studies have shown that you burn more calories throughout the day if you do cardio first thing in the morning. Truly though, the best time to do cardio is when you can push yourself the hardest. If you’re a morning person, great! But, if you aren’t don’t sweat it, literally. Just get it done later in the day once you’ve perked up. If you are looking to lose weight, you want to aim to do cardio four to six days per week. To maintain overall health, aim for 20-30 minutes of cardio 3 times per week.

HOW should I do my cardio?

Two to three of your weekly cardio sessions should include HIIT (High Intensity Interval Training). HIIT is a super-effective, fat-burning mode of aerobic exercise that consists of short bursts of high-intensity effort followed by a rest period. The push should take your heart rate up to about 86-95% of your HRmax.  The recovery period should bring your heart rate back down to 65-75% of your HRmax. If you don’t have a heart rate monitor, you can measure your push and rest based on the “talk test.” During your push, it should feel difficult, if not impossible, to get even one word out. During the recovery you should be able to hold a short conversation. The duration of push to rest will depend on your goals, current fitness levels, and the amount of time you want to spend.

The What, When, and How's of Cardio

This stuff works! HIIT training creates an EPOC in your body, or an post-exercise oxygen consumption. EPOC is the amount of oxygen required to restore your body to its normal, resting level of metabolic function (called homeostasis). It takes calories, lots of calories, to bring your body back to equilibrium after a high-intensity cardio sesh. EPOC is determined by intensity of exercise, not duration. Kicking your butt two to three times a week for a short amount of time will increase your post-exercise basal metabolism so you keep burning fat even after you’ve showered!

Try one of my HIIT workouts and let me know how bad*ss you feel! Then, show me your post-HIIT glow by posting a picture on Facebook, Instagram, or Twitter with #sweatinginmyspandex 🙂

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What’s your favorite type of cardio? Let me know in the comment box below! I may even use it to create a new workout post 🙂

Health and happiness,


Hi and welcome to Life in Spandex! I'm Emily, a personal trainer who believes there should be no secrets standing in your way to getting fit. I am sharing my knowledge here on this blog in order to help you reach your goals. Fitness should be fun, eating healthy should taste good, and feeling your absolute best is the ultimate goal. Let's get fit together!
  1. […] done a long run for a while because I’ve been concentrating more on strength training and HIIT for cardio. I still didn’t feel 100% when it was done, but I did feel a whole lot […]

  2. Reading this as I’m about to head to the gym! Great motivator!

  3. I am a CARDI-HOE! LOL!!!! I do entirely too much, but I love it and just cannot stop! It’s an addiction! 😉 That elliptical and I are in a serious relationship!

    1. Haha always love another cardio groupie! 😉 Glad to hear I’m not the only one who needs to be told to take the cardio down a notch :p

  4. Love me some HIIT. I never thought I’d cross over from distance running to CrossFit but once the hubby got me in the box I was hooked 😉 The whole lifting making me feel like a bad a$$ doens’t hurt either 😉

    1. Hell yes, Becki! love hearing how much you love lifting and intensity. Just make sure you have an instructor who guides you through proper form so you don’t get hurt 🙂

  5. Glad to hear I don’t have to do my cardio in the morning! I like to start off with yoga just to get myself loosened up and mentally ready for the day. In the evenings, I may run under the stars, when the sweltering Florida sun has gone to sleep. Great post!

    1. Thanks Rica! Yes, definitely enjoy your evening runs! Just make sure you finish at least 2-4 hours before bedtime so you don’t upset your sleep ?

  6. I also find that working out in the morning works best for me as I still have lots of energy to give.

    1. Totally agree! I have the most energy when I workout in the morning 🙂 What type of workouts do you like?

  7. Oh I love HIIT workouts! I wore a heart rate monitor for quite sometime during my workouts to keep my heart rate up. But after awhile i didn’t need that extra motivation anymore. The only motivation I need was the feel good feeling after a great workout:)

    1. That’s awesome, James! I experienced the same thing. My resting heart rate is so low that sometimes a heart rate monitor was discouraging because it takes SO much effort to get my heart rate up haha!

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