Can fitness levels impact heart rate variability readings?
Written by
David Nelson
Reviewed by
Prof. Graham Pierce, Ph.D.Your fitness level is a significant factor in heart rate variability patterns. I have often observed this relationship as a trainer. Cardiovascular conditioning always elevates resting variability. Very intense training always lowers readings for a temporary period of recovery. This reflects adaptation factors in the body.
Well-conditioned athletes will generally exhibit higher baseline scores, as their nervous systems are better equipped to handle the physical demands placed upon them. However, even elite competitors will experience drops in performance post-session (from intense training), and therefore the body will indicate that it has prioritized restoration. So the individual baselines matter more than comparisons between people.
Cardiovascular Conditioning
- Aerobic efficiency: Improved oxygen utilization enhances rhythm stability
- Resting HRV: Higher baselines in endurance-trained individuals
- Training response: Quicker recovery after moderate exercise
Strength Training Effects
- Neural adaptation: Heavy lifting temporarily lowers next-day readings
- Sympathetic activation: Power exercises stimulate stress responses
- Recovery need: Require longer restoration than cardio sessions
Overtraining Indicators
- Sustained drops: Consistently low readings across multiple days
- Performance decline: Strength and endurance plateaus
- Intervention: Immediate deload week with active recovery
Detraining Consequences
- Reduced adaptability: Lower HRV after two inactive weeks
- Fitness loss: Decreased VO2 max correlates with variability
- Restart protocol: Gradual intensity rebuilding over 21 days
Focus on your data rather than someone else's. Each of my clients has a different genetic makeup and history. A person who has been sedentary for years may be thrilled to reach 40ms, while an athlete may be trying to maintain 80ms, different but appropriate baselines for each person's particular physiology.
Make adjustments to your training based on the feedback from your heart rate variability. When those readings stay above your baseline, increase training intensity carefully. If readings remain low for an extended period, a recovery period is recommended. I modify client programs every week based on their morning measurements. This prevents clients from overtraining and allows them to maximize the benefits of their program.
Read the full article: Heart Rate Variability Explained Fully
