HRV may be used to determine an athletes recovery level after a hard day's training. Start off by taking a base line of HRV first thing every morning, before working out or coffee. Mornings when HRV is lower than the base line means that the athlete has not fully recovered from their previous workout or may even indicate that the individual is stressed out.
For more in-depth information, read the nerdy bits below.
Biomedical signals and analysis such as non-medical electrocardiogram (ECG) and heart rate variability (HRV) provide quantitative information about physiology and autonomic nervous system activity. Thus, biomedical signals are commonly used in objective assessment of well being and sports performance.
Personal monitoring and quantified-self are current trends where biomedical signal monitoring and analyses have a key role. For example, they can be used to objectively evaluate physical fitness, training effect and recovery time.
The sympathetic nervous system (SNS) increases heart rate, force of contraction, and blood pressure, leading to an increased blood flow to the muscles. Anytime an athlete has felt an “adrenaline rush” before a competition, this is essentially the SNS being stimulated to prepare for competition.
On the flipside, the parasympathetic nervous system (PNS) does the complete opposite and is responsible for reducing heart rate and blood pressure in the absence of stress. Essentially, the PNS helps facilitate recovery after a stressful event (e.g. competition) by counteracting the effects of the SNS.
Both the SNS and PNS are essential for performance and recovery. The SNS stimulates the body for the stressors experienced during performance, and the PNS is vital for recovery and regeneration. An “imbalance” between the SNS and PSNS can lead to reductions in athletic performance and overtraining.
HRV is also affected by mental and chemical stress as well as physical stress. Mental stressors such as job/work-related stress, making complex decisions, public speaking tasks, and performing tests/exams have all been shown to significantly reduce HRV. Athletes experiencing high levels of stress may make smaller strength gains than those with lower stress levels. In addition, chemical stressors such as alcohol have been repeatedly shown to reduce HRV.