Elite Physique The New Science of Building a Better Body

Assess to Impress
13
Cardiorespiratory Fitness
How much cardio do you need? The Center for Disease Control recommends
that adults perform at least 150 minutes of moderate-intensity activity, or at
least 75 minutes of vigorous-intensity activity, each week (U.S. Department of
Health and Human Services 2018). Preferably, this duration of aerobic activity is
spread throughout the week. Later in this book we cover workouts, consisting
of both resistance training and cardiorespiratory conditioning, that meet those
guidelines. For now, the goal is to find a simple way to measure how well your
cardiorespiratory system is working to drive your endurance, as well as a way
to test your progress.
You can test your cardiorespiratory fitness one of three ways, depending on
your current level of fitness. The least taxing option is the 1-mile (1.6 km) walk
test (Rockport walk test); the most challenging is the 1.5-mile (2.4 km) run, part
of the Navy Physical Readiness Test (Whitehead et al. 2012). Both of these distance-based
tests accurately correlate with an increase in V· O 2
max, a measure of
how well your body uses oxygen during exercise (Weiglein et al. 2011). The third
option is the 12-minute walk/run test popularized by Kenneth Cooper, founder
of the Cooper Institute (1968). All three tests are valid measures of cardiorespiratory
fitness (Mayora-Vega et al. 2016; Weiglein et al. 2011).
A key with any form of testing is to keep the variables as consistent as possible.
When you retest in the future, wear the same shoes and run on the same
surface. Indeed, there are significant metabolic differences between running on
a treadmill versus over ground (Miller et al. 2019). Neither is necessarily better,
so use whichever is most convenient for you, and stick with it for future testing.
For any of the following three tests it is important to first get clearance from your
physician.
1-Mile Walk, 1.5-Mile Run, or 12-Minute Walk/Run
These tests assess the health of the heart, lungs, and blood vessels as well as
the endurance of the lower extremities and respiratory muscles. Regardless of
the test you choose, perform it with as much effort as possible, as follows:
•
For the 1-mile (1.6 km) or 1.5-mile (2.4 km) run, make a note of the time it
takes from start to finish.
•
For the 12-minute walk/run, begin running and walk only when you don’t have
the energy to run during the test; make a note of the distance you traveled.
There are a few key points to mention here. First, if you choose to run on a
treadmill, set the incline to 1 percent, which better mimics the demand of running
over ground. Second, there is little consensus for recommended times or
distances for the aforementioned tests. Therefore, the best option is to compete
against yourself. Third, there are other ways to test your cardiorespiratory fitness
that might be more conducive to the activities you enjoy. For example, you could
test your distance using a stationary bike or rower over the course of 12 minutes,
thus mimicking the 12-minute walk/run test. Whatever test you choose, work to
increase your distance or time every four to six weeks.