HRV-Based Thresholds in Rowing: Validity and Reliability Assessment

Area of Science:

• Sports Science
• Exercise Physiology
• Cardiovascular Physiology

Background:

• Lactate thresholds (LT) are crucial for determining endurance performance in rowing.
• Assessing LT typically involves invasive blood sampling.
• Heart rate variability (HRV)-based thresholds (HRVT) offer a non-invasive alternative.

Purpose of the Study:

• To examine the concurrent validity and between-day reliability of rowing-specific HRVT.
• To compare the performance of HRVT1 and HRVT2 against established lactate thresholds (LT1, LT2).

Main Methods:

• 21 rowers completed two incremental rowing ergometer tests one week apart.
• Heart rate variability (HRV) and power output were recorded during tests.
• Concurrent validity and reliability of HRVT1 and HRVT2 were analyzed against LT1 and LT2.

Main Results:

• HRVT2 demonstrated good to excellent reliability (ICC=0.93) and low measurement error (SEM=6W, MDC=16W) for assessing LT2.
• HRVT1 showed lower reliability and higher measurement error for LT1.
• Concurrent validity was good to excellent for HRVT2 vs. LT2 (ICC=0.90) and sufficient for HRVT1 vs. LT1 (ICC=0.78).

Conclusions:

• Rowing-specific HRVT is a potentially valid and reliable method for estimating lactate thresholds.
• HRVT2 is a particularly promising and accurate surrogate for LT2 in rowing.
• HRVT offers a practical, non-invasive approach to LT assessment in athletes.