The most important findings from this study were:

• Traditional measures of 1-RM for muscle strength (or 70%

1-RM for muscle power) were better at predicting stair

climb power in young adults as compared to a hand-held

isometric MMT device

• Stepwise regression analysis showed that only hip MMT

strength (not knee or ankle) was significantly related to

1-RM strength

• Stepwise regression analysis also showed that only knee

MMT strength (not hip or ankle) was significantly related

to 70% 1-RM power or stair ascent power

• Stair climb power appears to exceed 70% effort in the

young women but not the young men

Strength: isotonic one-repetition maximal (1-RM) seated bilateral

leg-press (LifeFitness) using NSCA protocols

Power: isotonic leg-press power determined at 70% of 1-RM and

timed stair ascent using our portable 4-step device (in Watts)

Manual Muscle Tests: hand-held dynamometer to test muscle

strength of the hip (@ 90 flexion), knee (@ 60), and ankle (@ 0)

using a Lafayette MMT (#01163) device; high range setting

(Andrews, Thomas, & Bohannon, Physical Therapy, 1996)

• Traditional methods of measuring muscle strength and power

can be difficult, time consuming, and require expensive

laboratory equipment

• Small hand-held manual muscle testing (MMT) dynamometers

have been suggested for field measures of muscle function

• The purpose of this study was to determine if the individual

strength of the hip, knee, or the ankle (using MMT) could predict

lower-body muscular strength and/or power using traditional

measures (1-RM, 70% of 1-RM, stair ascent)

Methods

M. Redmond, S. Lenz, K. Murata, & T. Marcell Department of Kinesiology

Background

Results

Conclusion(s)

Future Directions

1

2

3

4

5

Leg press 1-RM and stair climb

power can be predicted by hip and

knee but not ankle strength in

young men and women

Funding Source:

CSU Stanislaus Research Fund

Table 1. Descriptive and muscle function test values (mean ± SD) for

the young adult subjects.

Leg press 1-RM strength (kg) was significantly correlated with

• 70% 1-RM measured power (W; r = 0.87, p = 0.001)

• Grip strength (kg; r = 0.80, p = 0.001)

• Stair ascent power (W; r = 0.63, p = 0.001)

• Hip strength (kg; r = 0.46, p = 0.007), knee strength (kg; r =

0.45, p = 0.008), but not ankle strength (kg; r = 0.26, p = NS)

The portable nature of the 4-step stair climb task and manual

muscle testing (MMT) could prove to be useful measures of

lower body function especially in the elderly

However, limitations to measuring strength using MMT (an

underestimation of force) may have impacted our findings

(Stone et al, J Rehabil Med, 2011)

Women Men

(n = 18) (n = 18)

Age (yr) 22.4 ± 3.9 23.6 ± 3.4

Height (cm) 165.7 ± 6.8 174.8 ± 6.5

Weight (kg) 67.1 ± 14.0 76.1 ± 14.5

BMI (kg/m2) 24.3 ± 4.0 24.8 ± 3.7

Body Fat (%) 24.7 ± 7.7 13.1 ± 6.6

Leg-Press Strength

1-RM (kg) 134.7 ± 38.0 227.0 ± 48.6

70%-RM (W) 379.1 ± 111.2 774.3 ± 292.0

70%-RM (W/kg) 5.7 ± 1.4 10.0 ± 2.5

Stair Ascent

Stair (sec) 0.76 ± 0.07 0.69 ± 0.09

Stair (W) 469.8 ± 89.0 593.0 ± 162.5

Stair (W/kg) 7.0 ± 0.7 7.7 ± 1.0

Manual Muscle Tests

Ankle (kg) 23.3 ± 7.6 29.9 ± 5.9

Ankle (W) 31.5 ± 22.4 46.3 ± 28.5

Knee (kg) 28.1 ± 8.4 32.4 ± 5.4

Knee (W) 55.7 ± 30.7 61.2 ± 33.3

Hip (kg) 24.7 ± 5.2 28.6 ± 4.5

Hip (W) 62.1 ± 24.0 67.8 ± 37.3

Total (kg) 152.1 ± 36.3 182.0 ± 19.4

Total (W) 298.6 ± 134.0 350.7 ± 147.2

Total (W/kg) 4.5 ± 1.9 4.7 ± 1.8