Wikipedia defines physical fitness as “a state of health and well-being and, more specifically, the ability to perform aspects of sports, occupations, and daily activities.”

Nerd Translation: Biologically, our physical abilities are made possible by our body’s systems working together to overcome a challenge. For example, climbing a big flight of stairs requires adequate power of various organ systems and metabolic pathways. An inefficiency of one or more of these systems may prevent a person from accomplishing a task.

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Whether a person is attempting to break a world record or prevent diabetes, fitness matters.

An aspiring Olympian is an example of peak performance. Their cardiorespiratory system, skeletal muscles, and/or mitochondrial functions have reached the limits of what is physiologically possible.

The average Joe may not have an aspiration of a gold medal. However, the process of aging and most cardiometabolic diseases lie at the opposite end of the spectrum of fitness. As we get older, even disability and death can be predicted by simple fitness assessments, such as grip strength or how fast you walk.

Running a marathon in under 3 hours requires a different set of skills than lifting a 300-pound barbell off the floor. How should we categorize the vast array of athletic abilities?

CrossFit describes ten categories of general skill: cardiovascular/respiratory endurance, stamina, strength, flexibility, power, speed, coordination, agility, balance, and accuracy. For general athleticism, a balance of these abilities is ideal. With respect to healthy aging and avoiding diseases, “endurance” and “strength” are probably the most crucial.

You may have taken the Presidential Fitness Test (PFS) as a child or heard of your kids doing a “PACER” test in PE class. These are attempts to grade a child’s fitness level. Although not perfect, these assessments are far more objective yardsticks than most adults use.

Many functional fitness tests have proven to be good predictors of general health, disease risk, and death. For example, a 2019 study showed the number of push-ups a 40-year-old man can do in one minute is strongly associated with future heart disease. In addition, a treadmill test performance (VO2 max) and quadriceps strength have shown to be good predictors of mortality in people over age 50.

Looking deeper at the tissues and physiology that enable fitness can be done in many ways. A person’s “percent body-fat” or “resting heart rate” are common examples, but this is just scratching the surface of what enables performance and longevity. Using modern technology and custom-designed protocols, we can gain deep insights into the function of your cardiorespiratory, neuromuscular, and metabolic systems.

While we often think of “stress” as harmful, it is a requisite for physiologic adaption. In the case of exercise, we place demands on a variety of organ systems and metabolism. In response, they grow or adapt. A stronger heart or skeletal muscle is built slowly, cell-by-cell. That biological progress can often be slow and difficult to perceive. This is especially true if the goal is weight loss or an improved physique.

A novice runner can likely get new PR in a 5K every few months with any consistent training. Losing the first 20 pounds is easier than the last 20 pounds. Unfortunately, progress isn’t always a straight line.

Improvements can often be elusive or frustrating. This is especially true for someone who is obese and seeking a transformation in their physique. Advanced athletes deal with the same when they hit a “wall” in the performance.

When progress stalls, we are often left wondering, “Why am I not improving?” or “Is this the best I can ever do?”.

Whether just starting a program or struggling to see progress, identifying your functional and physiologic weaknesses is essential. Improvements are often delayed due to misguided activities or even overtraining.

If you want to optimize performance or health, programming around these limitations is key. With FitnessDx, you can try smarter, rather than just trying “harder.”