Linnamo et al., Department of Biology of Physical Activity, University of Jyväskylä, Finland

FAM  frequency response  method as a tool to measure neuromuscular  and 

physiological recovery  after eccentric and concentric exercise  

 Baseline 

The purpose of this study was to examine if FAM

frequency response method can be used as a tool

to measure neuromuscular and physiological

recovery after eccentric and concentric exercise

performed by cycling dynamometer. Twelve

healthy male volunteer test subjects participated to

the study. Both eccentric and concentric

measurement session consisted of five

measurement: pre-fatigue, post-fatigue, 2h after,

2d after, and 7d after fatigue.

Measurements were:

1. blood sample

2. orthostatic test; heart rate (HR) variability

3. neuromuscular measurements 

4. FAM measurements

Results  

The results of this study shows significant

changes is leukocytes, lymphocytes, neutrophils,

IL-6, TNF-alpha and cortisol especially

immediately after and two hours after the

exercise. FAM-variables were found to correlate

strongly with some of the measured blood

variables, in particular with lymphocytes and

neutrophils which are inflammation markers

suggesting that the changes observed with FAM

may be sensitive to these markers. Serum CK

after eccentric exercise was also found to be

correlated with FAM indicating that FAM may

also be sensitive to muscle damage.

Neither exercise caused any major changes in HR

variables. However, several correlations were

observed between FAM and HR variables of

which the strongest ones were with HF power and

LF power. FAM may also be sensitive to the

changes in vagal and symphatic activity of the

autonomous nervous system.

Most of the neuromuscular variables showed that

the effect of eccentric exercise was more

pronounced after eccentric than concentric

exercise. Strongest correlations between

neuromuscular and FAM variables were found

after eccentric exercise in MVC whereas after

concentric exercise also variables related to power

correlated with FAM.

Main findings of the study were as follows:

1. Eccentric exercise led to a longer

recovery than concentric exercise which

was seen most clearly in FAM variables

and CK values.

2. Strongest correlations were found

between FAM variables and lymphocytes

and neutrophiles immediately and 2h after

after eccentric exercise

3. Several correlations were found 7d after

concentric exercise which was not the

case after eccentric exercise.

4. There did not seem to be any major

differences between the right and the left

side or between any single stimulation

intensity.