skip to Main Content
$300 loan.
A collage of four images of people utilizing heart-rate training while working out.

Figuring out exactly how much cardio you need can be tricky. Some fitness proponents will say that the right strength-training program provides enough, and that dedicated cardio isn’t necessary. Others will suggest that doing short bouts of high-intensity intervals a couple of times per week is all that’s needed. Still others will encourage daily cardio workouts to maximize health.

The total amount of cardio you need is one factor, but it’s also imperative to consider others, such as how hard you need to be working during your sessions and how often you do them. As you piece together your exercise plan, knowing which cardio exercises are best for you can be a real challenge when you don’t have the right tools or information.

While many people are fairly clear about their exercise goals, it can be easy to fall into a cardio routine that isn’t as beneficial as you may have originally hoped for.

As part of a balanced fitness program, cardio has a lot to offer when done the right way. Some of our favorite benefits include:   

Longevity: VO2 or cardiovascular capacity is one of the best predictors of long-term health and quality of life.

Mood/mental health: Aerobic exercise helps stimulate “feel-good” neurotransmitters and overall brain function.

Cardiovascular wellness: Exercise helps keep the heart and blood vessels healthy and resilient.

Immune health: Regular training helps stimulate and maintain healthy immune function

Recovery: Between harder training sessions, light-moderate cardio can improve blood flow and nutrient delivery to muscles that need repair.

Cardio Done Right: The FITT Principles

As is the case with any exercise program, effective cardiovascular training plans should utilize the FITT — Frequency, Intensity, Time, and Type — principles. The net effects of your training program depend on the overall FITT of training you choose, as well as your ability to withstand and adapt to the various stressors of the program (on top of the demands of life itself). 


Frequency pertains to the number of exercise sessions each week. How often you train is somewhat contingent on several factors, including the intensity of your workouts and the types of workouts, as well as your exercise goals and level of fitness. 

Frequency recommendation: three to five total cardio sessions per week 


Intensity relates to how hard you work during a given workout. Understanding how your body responds to a variety of workout intensities is critical when planning an effective cardio program. Each person burns fat and carbohydrates at varying rates, or at different intensities or heart-rate zones, which can be measured through assessments such as an Active Metabolic Assessment (AMA). You can also estimate training zones through the Silver Method, though they won’t be as accurate or detailed as an AMA.

Once zones have been identified, an individual’s ideal training intensities can be planned out to customize the cardio program and its goals. There are five heart-rate zones we use at Life Time:

Zone 1: Feels easy and conversational, like you could go for hours.

Zone 2: Breathing is a bit heavier, but you’re fairly comfortable and can still maintain a conversation without losing your breath.

Zone 3: Breathing feels heavy, and you are working harder but could still maintain the effort for 30 minutes or more if you’re fit.

Zone 4: You feel winded, and you’re pushing yourself very hard.

Zone 5: You can barely catch your breath, and you’re working at your absolute max.

Intensity recommendations:  

  • All-out, push-your-limits sessions: 1 to 2 times per week
  • Moderate intensity: 1 to 3 times per week
  • Easy, active recovery: 1 to 2 times per week


Time refers to how many minutes or hours you train each session or total for the week. The total time in your program will be dependent on your fitness level and the type of exercise you plan to do.

Time recommendations:

  • Hard sessions should be short — possibly as little as 10 to 15 minutes
  • Easier and moderate sessions should be 30 to 60 minutes, keeping in mind it may be more or less based on someone’s goals


Type refers to the style of exercise being performed. There are plenty of exercise types to choose from, making this component of the FITT principles one of the easiest things you can do to change up your routine.

Type recommendations:

  • Prioritize variety and enjoyment when choosing your cardio method
  • Machines, such as treadmills, rowers, stair climbers, or elliptical trainers are awesome for being able to measure progress over time
  • Moving around outside or in free space are great for mental enjoyment

Without the right type of structure or inclusion of purposeful exercise, we can end up frustrated that our efforts aren’t yielding the results we’re expecting. If this is something you’re experiencing, it may be time to reevaluate what areas of cardio you may be getting wrong. 

Cardio Gone Wrong: Four Mistakes to Avoid

When there is no plan in place or we’re training based on how we feel, it can hold us back from seeing the results that we’re working so hard to achieve. 

1. You’re doing cardio, but moving less the rest of your day.

Think about this for a second: You wake up early, get to the gym and work your butt off for a solid hour, spinning your legs until they feel like mush. A puddle of sweat surrounds your bike, and your heart-rate monitor says you burned a massive 950 calories during your hour in the pain cave.

Great, right? Maybe. Until later in the morning or early afternoon, when you forgo your normal walking break because you feel extra worn out today. Or later that evening, when you opt to catch a nap before dinner rather than walking the dog or mowing the lawn.

It happens more than you realize, but people tend to justify inactivity in the hours after a strenuous workout. And since continuous, vigorous training drains so much energy, we may turn into an inactive couch potato unless we make a conscious effort to stay active outside of the exercise sessions.

For health purposes, it’s helpful to get plenty of low-intensity movement, but most experts recommend getting the majority of that movement throughout your day instead of condensing it into one particular segment of the day.

The bottom line: Have fun with your exercise sessions, but stay moving throughout the entire day, too.

2. You’re doing too much.

When it comes to cardio, more isn’t always better or even necessary — especially if you’re doing more cardio than your body is able to recover from. That said, the health benefits of cardiovascular training appear to begin after around 30 minutes of moderate intensity most days of the week (four to five workouts totaling more than 150 minutes).

Doing long sessions (between 60 and 90 minutes) is rarely necessary unless you’re training for a specific event that will last longer than this amount of time. Evidence suggests you’re better off capping your strict cardio time to about 30 minutes or so, and including several days per week of resistance training for general body composition and weight improvements.

The bottom line: More cardio isn’t better. A moderate amount of higher-quality cardio is best.

3. All your cardio sessions are the same.

In a way, cardio can be helpful for getting a little solitude, for zoning out, or for relaxing. However, doing the same workout every day when you’re looking for results is definitely not going to work.

A good cardio program (or overall exercise program, for that matter) incorporates a tremendous amount of variability from workout to workout — variability of intensity, that is. Our bodies have a few major energy systems that all need to be challenged progressively over time.

This leads us back to the importance of heart-rate training and knowing your zones through completing an Active Metabolic Assessment. Knowing your personal heart-rate zones will help you identify the types of cardio workouts you should do per week that properly force your body to develop new fitness capacity and drive results.

The bottom line: Your cardio plan should include a wide range of intensities from session to session.

4. “Cardio” has become synonymous with “I get to eat extra calories without consequence.”

Do you spend several hours each week working out so you can “allow” yourself little indulgences? Squeeze in an extra session of cardio so you don’t feel bad eating “off plan?”

While exercising to burn off some energy may give you a little room for forgiveness — perhaps even prevent additional weight gain — exercising to prepare for or undo poor eating choices aren’t guaranteed to help you see great results. Large amounts of cardio training have been shown to induce compensatory eating patterns, especially in women.

I totally get it. It’s easy to get into this mathematical mindset despite knowing that exercise is far more than just a way to expend calories. Exercise can be a potent stimulus, good or bad.

Well-planned, properly executed bouts of activity can stimulate your body to experience incredible changes in fitness and improve health or body composition — provided you also have a stellar recuperation strategy.

The bottom line: You can’t outrun bad food choices.

When it comes to cardio, there’s a lot to consider when coming up with a plan and strategy that is most effective for you and your goals. Instead of settling for what feels best or what you’ve always done, make sure your cardio regimen is personalized, purposeful, and gets you closer to your goals. If you’re looking to optimize your cardio plan, our team of coaches and health experts are available to help you take the next step. You can get connected here if you’re a Life Time member, or here if you’re not currently a Life Time member.

Keep the conversation going.

Leave a comment, ask a question, or see what others are talking about in the Life Time Training Facebook group.

Paul Kriegler, RD, CPT

Paul Kriegler, RD, LD, CPT, CISSN, is the director of nutritional product development at Life Time. He’s also a USA track and field coach.

Thoughts to share?

More From Life Time

A trainer instructing a client using a medicine ball.

Personal Training

Life Time Personal Trainers create a plan that suits your body, taps into your strengths, and delivers results.

Connect With a Personal Trainer


More Like This

Danny King

All About Heart-Rate Training: How to Use it to Maximize Your Fitness Efforts

With Danny King, Master Trainer
Season 5, Episode 10   June 21, 2022

Heart rate can be a powerful tool for building fitness and seeing results from your exercise regimen. Danny King, Master Trainer, shares what to know about heart-rate training, including what it is, how to use it in your workouts, and the ways you can identify the key metrics needed for yourself.

Listen >
A Life Time fitness professional speaking with four members in workout wear.

Do You Need a Personal Trainer — Or a Fitness Professional?

By Paul Kriegler, RD, CPT
Three traits to look for when choosing someone to help with your fitness efforts.
Back To Top