The modified D-max is a valid lactate threshold measurement in veteran cyclists

Area of Science:

• Sports Science
• Exercise Physiology
• Aging Research

Background:

• Aging impacts athlete response to training.
• Understanding physiological markers in veteran athletes is crucial for effective training.

Purpose of the Study:

• To compare power output (PO) and heart rate (HR) at the D-max lactate transition threshold with mean values from a 30-min time trial (TT30) in veteran cyclists.
• To validate the D-max threshold as a predictor of sustained exercise intensity in older athletes.

Main Methods:

• Nine veteran cyclists (>= 35 years) underwent an incremental exercise test to determine D-max PO and HR.
• Participants completed a 30-min laboratory time trial (TT30) to measure average PO and HR.
• Statistical analysis, including correlation and Bland-Altman plots, compared D-max values with TT30 results.

Main Results:

• PO and HR at D-max were significantly correlated with mean PO and HR during the TT30 (r=0.95 and r=0.88, respectively).
• Bland-Altman analysis showed close agreement between D-max and average TT30 values for both PO and HR.
• The D-max method demonstrated high accuracy in predicting sustained exercise intensity.

Conclusions:

• The D-max lactate transition threshold is a valid and accurate method for prescribing training intensity in veteran cyclists.
• This finding supports the use of D-max to determine the highest average power output and heart rate sustainable during prolonged exercise in older athletes.
• The D-max method offers a practical tool for optimizing training for aging athletes.