2.9.08 Math Math and yes, More Math

Day of the in class demonstration of the bike ergometer GXT.

As stated in the title, this is a lot of math. If you weren't there, I would suggest getting together with Tom or someone else. Pretty in-depth lecture.

ACSM pg. 289 pkt. pg. 14 VO2

How much oxygen is a person taking in and consuming at a given level of submaximal exercise?

Walking test: Usually on a treadmill-must control speed

Stationary bike: cannot be used on just any stationary bike-must provide info on workload. Ergometer (work measure)- can measure workload.

Arm ergometer:arm cranking- generally for people who cannot use bike, lower extremity problems.

Stepping test: Macartyl Step test

We use these equations to estimate submax VO2. There is a linear relationship between HR & VO2. Relationship begins over 110HR.

GRAPH

Our major goal is to get two data points to estimate VO2max. Need age to estimate HRmax.

Say we have two people who are 30 years old. They both should be able to get to a HR of 190 (200-30).

Walking:
Best used at speeds from 1.9 mph-3.7 mph as long as they are truly walking.

VO2= (.1)(s)+(1.8)(s)(g)+3.5

Where s=speed of treadmill (reported in meters/min.)
g=grade or incline (1% = .01)

miles per hour x 26.8 = meters per min.

mpm/26.8 = miles per hour

VO2 = HC + VC + RC

HR is horizontal component (distance or speed)
VC is vertical component (incline or grade)
RC is the rest component (VO2rest)

VO2rest is .1m/kg/min to get 1m in 1 min. (for everyone)
The difference is the HR it takes to do this.

Say we get on the treadmill going 4mph.

VO2 = .1(4x26.8)+0+3.5= 10.72+3.5= 14.22 ml/kg/min (pg. 289-all units are ml/kg/min)

What about 4mph with a 12% grade?

VO2= .1(107.2)+1.8(107.2)(.12)+3.5= 37.3752 ml/kg/min.

Running: Best used at speeds of 5mph but can be used with validity from 3-5mph.

VO2= (.2)(s)+(.9)(s)(g)+3.5

.2 is because it takes twice as much oxygen to run at the same speed as it does to walk.

La Luz Trail: 12% grade 9 miles long 1hr.: 45min. (105 min.)

9/105min. x 60min./hr. = 540 (5..14 mph)

.2(137.752)+.9(137.752)(.12)+3.5= 45.93ml/kg/min.

pkt. pg. 16 MEMORIZE kcals/min.

METS x 3.5= VO2 so VO2 x BW(in kg)/ 200

(45.93 x 71kg)/200 = 16.39 kcals/min. x 105 min. = 1720.8 kcals burned going up LLT.

Bike Ergometer:

VO2 =1.8 (workrate/BW in kg) +3.5+3.5

workrate is resistance & cadence (Friction is measured in kg or kp (kiloponds))

kg and kp are THE SAME

Workrate = kg x m/rev. x rev./min.

kg is the friction
m/rev is dependent on the bike ergometer type: Monarch =6, Bodyguard & Tunturi =3
rev/min is the cadence (dictated by the protocol being used)

Pg. 74 ACSM
Pg. 27 pkt.

Example: Monarch, 90rpm, 1.5 kp

1.5x6x (90/min)=(810 kgm/min)/ 6 = 135 Watts (power a lightbulb for one min.)

Maryann's Bike Ergometer Test YMCA Protocol

Pg. 84 pkt.

I 0-1 nothing
1-2 15 HR, 7RPE
2-3 145/80, 16HR, 7RPE

Pg. 74 (1.5 kg @ 50rpm)

II 3-4 nothing
4-5 18HR, 8RPE
5-6 155/80, 18HR, 9RPE

III 6-7 nothing
7-8 20HR, 14RPE
8-9 165/78, 22HR, 14RPE
9-10 175/80, 22, 15RPE

HRmax =220-54

70%= 116 (19HR)
85% = 141 (23HR)

Weight 205/ 2.2= 93.18 kg

Cool down is 4 min. (collect everything for all 4 min.)

10-11 175/80, 19HR, 12RPE
11-12 170/70, 17HR, 11RPE
12-13 165/75, 16HR, 11RPE

VO2= 1.8 (1.5x6x50)/93.18+3.5+3.5= 15.69 ml/kg/min.

Mathmatical formula to extrapolate HRmax
b=slope= (SM2 - SM)/ (HR2 - HR)

VO2max = SM2 + b (HRmax - HR2)

b= (18.59 - 15.69)/ (132 - 108) = .12

VO2 max = 18.59 + .12 (166-132)
VO2 max = 22.67 VO2 peak probably

pg. 46 pkt. Average Category
pg. 47 For biking program 50-60% of VO2max
Fat loss-closer to 50
Interval 60-50-60-50 etc.

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