Heart rate-based lactate minimum test: a reproducible method.
OBJECTIVE
To find the individual intensity for aerobic endurance training, the lactate minimum test (LMT) seems to be a promising method. LMTs described in the literature consist of speed or work rate-based protocols, but for training prescription in daily practice mostly heart rate is used. The aim of the present study was to investigate the reproducibility of a new heart rate-based LMT protocol.


METHODS
20 subjects each underwent four LMTs on a cycle ergometer. The LMT consisted of a first part (Conconi test) to induce lactate accumulation and a second part (incremental protocol) with stages of 5 min starting beyond the aerobic threshold. During these stages work rate was adjusted to reach predetermined heart rates, which were calculated for every single test from heart rate (HR) at rest and maximum HR. Lactate was measured after each stage to define the lactate minimum (LM) and the corresponding HR.


METHODS
Institute of Sports Medicine.


METHODS
20 healthy and endurance-trained individuals (13 men, seven women).


METHODS
Reproducibility of heart rate at LM.


RESULTS
The reproducibility of heart rate at LM was high (coefficient of variation (CV) = 2.1%). The reproducibility of work rate at LM was good (CV = 6.7%). CV for lactate concentrations at LM was 17.4%. High interindividual differences at LM were found in heart rate (range 149-178 beats/min) and lactate levels (range 1.2-6.8 mmol/l).


CONCLUSIONS
The LMT using a heart rate-based protocol is a reproducible method of assessing HR at an exercise intensity where an equilibrium exists between blood lactate accumulation and elimination.
Strupler
M
M
Swiss Paraplegic Centre Nottwil 6207, Switzerland. matthias.strupler@paranet.ch
Mueller
G
G
Perret
C
C
D000328:Adult; D002985:Clinical Protocols; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test / Q000379:methods* / Q000592:standards; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D007773:Lactates / Q000378:metabolism*; D008297:Male; D010101:Oxygen Consumption / Q000502:physiology; D010807:Physical Endurance / Q000502:physiology*; D015203:Reproducibility of Results; D013647:Task Performance and Analysis; D055815:Young Adult
D007773:Lactates