Caloric Expenditure and Physiological Responses During and Following a

Suspension Training Workout

Sigma Xi Brown-bag Lunch October 16, 2009Dr. Wes Dudgeon

BackgroundWhat is TRX ® /suspension training?

Body Weight resistanceUnstable surfacesRequires “Core” muscle use for all exercisesEmphasizes flexibilityInterval-Type training

Where do we (I) come in?Many claims made by manufacturer,

but……… No Data to Back it up!!

Research questions we asked (this time):What is the “stress” placed on the body by a

TRX® workout? (HR, BP, RPE)What is the “metabolic effect” of a typical

TRX® workout? (caloric expenditure, substrate usage)

Study DesignDescriptive study

9 college age males (21.4 0.9 years, 176.7 3.3 cm, 68.8 3.6 kg, 13.4 1.7% body fat)

2 Familiarization sessionsTesting day included:

BodPod for body fat %, Fitting of a HR monitor, attachment to Metabolic Cart® (ParvoMedics), insertion of indwelling venous catheter

30 min resting energy expenditure 60 min training session 120 min cool down

Variables of InterestHRBPRespiratory Exchange Ratio (RER)Caloric Expenditure (kcals/min)Blood Lactate

•food + O2 CO2 + H2O + energy (ATP) •RER = VCO2 / VO2 •reflects ratio of CHO and fat metabolism

• 100% CHO metabolism, RER = 1.0e.g. C6H1206+6 O2 6 CO2 / 6 O2 = 1.0

• 100% fat metabolism, RER = 0.7e.g. C16H32+23 O2 16 CO2 / 23 O2 = 0.7

• 1:1 CHO to fat ratio, RER = 0.83

assumes (incorrectly) no protein is used

Example Testing Session

Pre Ex-ercise

Mid Ex-ercise

Post Exer-cise

30 min Post Exer-cise

60 min Post Exer-cise

120 min Post Exer-cise

0

20

40

60

80

100

120

140

160

0

20

40

60

80

100

120

140

Systolic

Diastolic

Heart Rate

Time

Blo

od

Pre

ss

ure

(m

mH

g)

He

art

Ra

te (

bp

m)

MID POST Session1

2

3

4

5

6

7

8

9

10

Exercise

RP

E (

1-1

0 S

ca

le)

Set 1 Exercise

Set 1 Recov-

ery

Set 2 Exercise

Set 2 Recov-

ery

Grand Exercise

Grand Recovery

Total0

20

40

60

80

100

120

140

160H

ea

rt R

ate

(b

pm

)

Grand Exercise Grand Recovery Total50

55

60

65

70

75

80P

erc

en

t H

ea

rt R

ate

of

Es

tim

ate

d M

ax

ima

l H

ea

rt

Ra

te (

%)

Pre Mid IP Post 30 Post 60 Post 1200.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

9.0

-18

-16

-14

-12

-10

-8

-6

-4

-2

0

Lactate PV Change

Time

La

cta

te (

Mm

ol/

L)

Pla

sm

a V

olu

me

Ch

an

ge

RMR EX EPOC0

50

100

150

200

250

300

350

400Total Caloric Expenditure

Tota

l K

cals

#

# = great than both RMR and EPOC

RMR EX EPOC0.600000000000001

0.700000000000001

0.800000000000001

0.900000000000001

1

1.1

1.2RER

RMR EX EPOC0

2

4

6

8

10

12

14

16

Oxygen ConsumptionV

O2 (

ml/

kg/m

in)

#

# = great than both RMR and EPOC

ConclusionsEffective method of burning calories, while

also providing additional caloric expenditure above baseline during a two-hour recovery

Using 30 sec work intervals followed by 60 sec rest periods elicited lactate and heart rate responses indicative of moderate intensity exercise

Carbohydrates were the primary fuel source during the TRX workout, while lipids were the predominant source during recovery