validity and test-retest reliability of the Steep Ramp Test in elderly persons

Clinimetrics is important to evaluate and to understand the health status and
progress of diseases in elderly. Interventions to improve exercise habits
require good baseline. Endurance should be measured at baseline. It is
important to understand the physical fitness to establish a good workout
intensity to evaluate training. This makes the physical therapy more
transparent and improves quality.
To determine physical fitness VO2max (maximal oxygen uptake) is one of the most
common used parameters. The gold standard is the Cardiopulmonary Exercise Test
(CPET). The CPET is a cycle test which measures oxygen uptake by gas analysis
and heart rate. The test takes a lot of time. The CPET is expensive due to
special analysis equipment and the need of trained personnel to carry out the
test. Due to the costs and the need of trained personnel, the CPET is not often
present in primary care and physiotherapy clinics. The physiotherapist needs a
short test that does not require specially trained personnel or expensive
equipment.
Currently the Astrand test is a widely used exercise test, but it is not a
useful test for clinical practice.
The Steep Ramp Test (SRT) is a short test for physical fitness. The SRT can
calculate an estimate of VO2max. The test takes about 6 minutes, including
warm-up. This test has a simple protocol in which every 10 seconds the wattage
is increased by 25Watt. No gas analysis or pulse measurement is required. This
test is easy to perform , takes little time and does not require special
equipment.
Multiple studies have proven that the SRT is valid and reliable for various
populations. This test is originally designed to determine the exercise
intensity of an interval training at patients with chronic heart failure. It
has been shown in earlier research subjects went to their limits, but their
heart rate and blood pressure during the SRT remained relatively low compared
to the CPET. SRT seems a good clinical suitable and useful test to measure
endurance in elderly in primary care. However the reliability and validity of
the SRT in elderly is unknown.

The aim of this study is to determine the criterion validity and test-retest
reliability of the Steep Ramp test to measure endurance in elderly aged 55
years and older. To examine the criterion validity of the SRT in elderly, the
test will be compared to the CPET. The CPET is regarded as gold standard.
Reliability is examined by the test -retest reliability

This study is a validity and reliability study. Participants will perform twice
the SRT and perform one CPET on three different test days. First, the validity
examination is performed in which the order of the tests will be randomized.
Then, there will be a second SRT.
The Workrate peak (WRpeak) of the first SRT will be compared with the WRpeak of
the second SRT for reliability. To examine the validity of the WRpeak the SRT
will be compared with the VO2peak of the CPET. Two questionnaires *Nederlandse
Norm Gezond Bewegen* (NNGB) and *Groninger Frailty Index* (GFI) will be
completed and anthropometric measurements will be done.

Participants perform twice the SRT and once the CPET. The participants
completed questionnaires NNGB and GFI. The exercise tests and questionnaires
are standard tests and questionnaires from clinical practice.
The SRT demands maximum peripheral load. It has no complications in previous
studies in patients with poor physical fitness. The CPET is a maximum test. In
general there are few complications in this test. Through proper screening,
complications can be reduced even more.
In this study people with cardio respiratory disorders, cardiovascular
disorders or musculoskeletal disorders who are not allowed to exert maximum,
will be excluded. If pressure or pain on the chest, dizziness or other form of
illness have been experienced by a researcher or participant, the test will be
stopped immediately. The test will also be stopped when the saturation
decreases with more than 5% or will be lower than 85%.
By performing this study, it may be possible to replace the CPET by the SRT.
The endurance measurement with the SRT is less demanding for the participants
and involves less costs involved for the performers.