The term “physical fitness” is used to characterize everything from a person’s physique to their general health and athletic performance. But while different definitions leave some room for subjective interpretation, most share five components of fitness in common.
So, what are the five components of physical fitness and, more importantly, what can you do to develop them?
What Are the 5 Components of Fitness?
To promote optimal health, focus on these five components of physical fitness: cardiorespiratory capacity, strength, endurance, body composition, and mobility.
1. Cardiorespiratory capacity
According to Trevor Thieme, C.S.C.S., Openfit’s senior manager of fitness and nutrition content, cardiorespiratory capacity (a.k.a. aerobic capacity or VO2 max), is the maximum amount of oxygen the body can utilize during intense exercise. “It relates directly to endurance,” he explains. “The more oxygen your body can utilize, the longer you can maintain a high level of effort.”
How to improve it: Thieme explains that one of the best ways to increase your aerobic capacity is to train at or near your lactate threshold — the point at which your body starts producing metabolic waste faster than it can remove it. This typically occurs at around 80 percent of your maximum heart rate.
Thieme says: “If you’ve ever felt a deep burn in your muscles, you know how it feels to reach the lactate threshold.” You can get there through activities like high-intensity interval training (HIIT), running hills, or playing sports that involve repeated bursts of all-out effort, like basketball and soccer.
Strength is the amount of force you (or more specifically, your muscles) can produce. Even if you don’t have plans to enter any weightlifting competitions, muscle strength is still an important component of fitness, as it affects your ability to perform everyday tasks like carrying grocery bags and moving furniture. In fact, the Centers for Disease Control and Prevention recommends that all adults engage in strength training at least two days a week.
How to improve it: Increased muscle strength comes with resistance training, but you need to be deliberate with your sets, reps, and rest periods, says Jonathan Jordan, CPT, a San Francisco-based trainer and nutrition coach. “For clients mainly interested in pure strength, I typically keep them in the 3-10 reps/4-6 sets range, where they’re at or close to failure on the last rep,” he says. One to two minutes rest between sets is optimal.
Not a fan of pumping iron, or simply don’t have access to barbells and dumbbells? “Bodyweight and gravity are all you need to build strength and muscle as long as you challenge yourself,” says Thieme.
There are two forms of physical endurance: muscular and cardiorespiratory. Muscular endurance refers to how long a muscle can perform work before fatiguing. Cardiorespiratory endurance is the ability of the heart, lungs, and blood vessels to deliver oxygen to working muscles during sustained activity.
Muscular endurance comes into play when you’re trying to bang out a set of, say, 20 push-ups or 15 curls. Cardiorespiratory endurance is what you rely on when you go for a long run or perform high-intensity interval training (HIIT).
How to improve it: To build muscular endurance, resistance training needs to target Type I (a.k.a. slow twitch) muscle fibers. Thieme recommends focusing lighter loads and higher reps. “In practice, that means doing 4-5 sets of a given exercise with a weight that challenges you to complete 12-20 reps per set,” he says.
Cardiorespiratory endurance increases by engaging in aerobic activity that challenges your heart and lungs. You can achieve this via moderate-intensity exercise like long-distance running and cycling, or high-intensity activity like sprinting and interval training.
4. Body composition
According to Thieme, body composition, the body’s ratio of lean mass to fat mass, is only an accurate indicator of physical fitness when considered in the context of the other components of fitness.
“The reason is that an overweight person who works out consistently is going to be fitter (and healthier overall) than a thin person who never or rarely works out,” he explains. “That said, if you’re overweight, you won’t be considered as fit as your workout partner if that person is leaner than you — even if you perform the same workouts every day — because carrying excess fat stresses the body.”
Body composition can be assessed by a professional, or you can estimate it with a home scale equipped to measure body fat. Women should aim for a body fat percentage of less than 24. Men should try to get under 17 percent.
How to improve it: According to Thieme, anyone looking to reduce their body fat percentage should dial in their diet. “It’s more important than exercise when it comes to fat loss, but you need both to optimize results,” he says.
Start by reducing your intake of processed foods and eating more veggies, lean protein, and whole grains. As for exercise, “the most effective form for fat loss is high-intensity interval training (HIIT), followed closely by strength training and distantly by low-intensity cardio, like jogging,” Thieme says. “But as long as you challenge yourself consistently, you will see results.”
Mobility, which encompasses flexibility, refers to your ability to move a joint through its full range of motion. “Improving your mobility can not only reduce your risk of injury, but also help you unlock greater strength,” says Thieme. “The stronger you are through a full range of motion, the more your strength will translate beyond the weight room.”
How to improve it: One of the simplest ways to improve your mobility is to always perform exercises using proper form and a full range of motion (or as close to it as you can). Stretches and exercises specifically designed to increase mobility can also help, and should be performed at least a few times a week.
Jordan says: “Rather than spending 60 minutes once a week on mobility, spending 10 minutes every day yields safer, more effective results.” Mobility work can easily be incorporated into a warm-up, cool down, or rest-day activity.