Background: Cardiovascular capacity, expressed as maximal oxygen uptake (VO2max),
is a strong predictor of health and fitness and is considered a key measure of physiological function
in the healthy adult population. The purpose of this study was to validate a specific step test
(StepTest4all) as an adequate procedure to estimate cardiovascular capacity in young adults. Methods:
The sample was composed of 56 participants, including 19 women (aged 21.05 2.39 years,
body mass = 57.50 6.64 kg, height = 1.62 0.05 m, body mass index = 22.00 2.92 kg/m2) and
37 men (aged 22.05 3.14 years, body mass = 72.50 7.73 kg, height = 1.76 0.07 m, body mass
index = 23.34 2.17 kg/m2). Participants were included in one of the following groups: (i) the group
used to predict the VO2max, and (ii) the group used to validate the prediction model. All participants
performed the StepTest4all protocol. The step height and the intensity of the effort was determined
individually. Heart rate and oxygen uptake were measured continuously during rest, effort, and
recovery phases. The validation process included the following three stages: (i) mean data comparison,
(ii) simple linear regression, and (iii) Bland–Altman analysis. Results: The linear regression
retained, as significant predictors of the VO2max, sex (p < 0.001) and heart rate recovery for one minute
(p = 0.003). The prediction equation revealed a high relationship between measurements (R2 = 63.0%,
SEE = 5.58). The validation procedure revealed non-significant differences (p > 0.05) between the
measured and estimated maximal oxygen uptake, high relationship (R2 = 63.3%), and high agreement
with Bland–Altman plots. Thus, VO2max can be estimated with the formula: VO2max = 22 + 0.3
(HRR1min) + 12 (sex), where HRR1min is the magnitude of the HR decrease (bpm) in one minute
immediately after the step was stopped, and sex: men = 1, women = 0. Conclusions: The StepTest4all
is an adequate procedure to estimate cardiovascular capacity, expressed as VO2max, in young adults.
In addition, it is possible to determine the qualitative level of cardiovascular capacity from the heart
rate recovery for one minute, more specifically, poor: <20, moderate: 20 to 34, good: 35 to 49, and
excellent: 50. This procedure has the benefit of being simple to apply and can be used by everyone,
even at home, without specialist supervision.
This research was funded by the Project “GreenHealth-Digital Strategies in biological assets
to improve well-being and promote green health” (Norte-01-0145-FEDER-000042), supported by the
Regional Operational Program of Northern Portugal (NORTE 2020), under the PORTUGAL 2020
Partnership Agreement”. This research was supported by Portuguese Foundation for Science and
Technology, I. P. (project UIDB/DTP/04045/2020)”.
