Assessing Cardiovascular Endurance

6 minute walk test  

Chair Step Test (Everett Smith), Bottomley p. 461
The patient is seated in a standard 18” chair with no arms. A bar is placed in front of the client that is as far away as needed to require almost full knee extension to touch it. The height of the bar is 6 inches. Prior to performing the test, take heart rate a couple of times. Having a metronome is ideal but not necessary. Set metronome to 60 beats/min.

Stage 1. Touch the bar with alternating feet 60x/min for 3 full min. Record HR. 
VO2 =8 ml/kg/min - 2.3 METS
Stage 2. Move the bar height to 12”. Repeat touching the bar with alternating feet. Do the task for 3 minutes and record HR. V02 =10 ml/kg/min - 2.9 METS
Stage 3. Move the bar height to 18”. Do alternating foot touches, one/second, for three full minutes or fatigue. Take HR. V02 = 12.3 ml/kg/min.- 3.5 METS
Stage 4. The bar remains at 18 inches. Arm activity is added to the leg activity. So, while patients are reaching with one leg toward the bar, they are simultaneously raising the arm on the same side to shoulder height. Take HR. V02 = 13.7 ml/kg/min. - 3.9 METS

HR (220-age) is used as a proxy for V02. Alternative, use Borg’s scale of perceived exertion. It correlates well with intensity of physical demand.

Step Test – ACSM 6th edition, p. 305, 75; Bottomley p. 461
Stepping is traditionally performed in a four-part process of lifting one leg onto a box or other fixed object, then pushing with this leg to raise the body and place the other leg on the box, then stepping down with the first and then second leg.  
Step Height: men-40cm, women 33cm; rate of 22.5 step-cycles/min; for 3 min (or longer if tolerated). (Astrand & Rhyming)  Quadriceps strength may not be adequate for some elderly participants.
Check HR and BP before and immediately after.  Include a warm up and cool down.

Modified Balke Test
Record resting HR. The entire test is run on a treadmill set at 2.0 mph which is usually do-able by older adults. The test requires a treadmill that can be adjusted upward in height. There are 6 stages that correspond to specific MET or oxygen demands as follows:

Stage 1. Grade =0. Walk @ 2 mph for 3 min. Record HR V02 =7.0 ml/kg/min. 2.0 METS
Stage 2. Grade=2%. Walk @ 2 mph for 3 min. Record HR. V02 =8.9 ml/kg/min. 2.5 METS
Stage 3. Grade=4%. Walk @ 2 mph for 3 min. Record HR. VO2= 10.8 ml/kg/min 3.1 METS
Stage 4. Grade =6%. Walk @ 2 mph for 3 min and record HR. V02= 12.7 ml/kg/min 3.6 METS
Stage 5. Grade=8%. Walk @ 2 mph for 3 min and record HR. V02= 14.6 ml/kg/min 4.2 METS
Stage 6. Grade=10%. Walk @ 2 mph for 3 min and record HR. V02= 16.5 ml/kg/min 

The formula 220-age is again used to get a relative idea of how much of a demand each step of the test requires. Perceived exertion is another way of getting to the same information.