REF-362 · Javaloyes et al., 2019 · International Journal of Sports Physiology and Performance, · Paper

Training Prescription Guided by Heart-Rate Variability in Cycling

17 well-trained cyclists, 8 weeks: the HRV-guided group improved peak power (+5.1%), power at VT2 (+13.9%) and 40-min TT (+7.3%) while the traditional group did not, but the between-group difference was not significant

Blimited evidenceMeasured on trained to highly trained athletesWritten before October 2026, being re-checked

Participants

n=17 well-trained road cyclists, divided into an HRV-guided group and a traditional-periodization group.

Protocol

1 initial evaluation week; 4 baseline weeks of standardized training to establish each rider's resting HRV; then 8 training weeks, with daily prescription in the HRV group based on the rider's HRV versus a predefined programme in the traditional group.
Evaluation weeks before and after the training period: graded exercise test (VO2max, peak power output, VT1 and VT2 with their power outputs WVT1 and WVT2) and a 40-min simulated time trial.

Key Findings

HRV-guided group improved peak power output (+5.1% [4.5%], P = .024), WVT2 (+13.9% [8.8%], P = .004) and 40-min time-trial performance (+7.3% [4.5%], P = .005); VO2max and WVT1 were unchanged.
The traditional-periodization group did not improve significantly.
There were NO significant differences between groups. Magnitude-based inference showed a likely beneficial effect for the HRV-guided group in the 40-min TT and a possibly beneficial effect in peak power output.
Authors' conclusion: daily HRV-based prescription "could result in" better performance enhancement than traditional periodization in well-trained cyclists.

Practical Application

In 17 well-trained cyclists, 8 weeks of daily HRV-guided prescription improved peak power (+5.1%), power at VT2 (+13.9%) and 40-min time-trial performance (+7.3%) while the traditional-periodization group did not improve significantly — but the difference between groups was not statistically significant (magnitude-based inference: likely beneficial for the TT, possibly beneficial for peak power). So HRV-guiding is a reasonable way to place hard days for a well-trained rider, not a proven upgrade over a good fixed plan.
Inference, not tested: the plausible mechanism is that hard sessions land on days the athlete can absorb them; the study did not measure session quality or total load, so "more efficient stimulus" is not shown here.
Not from this paper; the base's own practice: which HRV threshold triggers a swap to an easy day, and which devices or apps to use, are house practice; the underlying HRV-monitoring evidence is Plews 2013 REF-361 and wearable validation in REF-364.

Limitations

n=17 split into two groups; the abstract gives no group sizes and reports no significant between-group difference — the "better" conclusion rests on magnitude-based inference.
8 training weeks; long-term effects not studied.
Well-trained cyclists; transfer to novices or to inconsistent athletes untested.
The Bellenger 2016 systematic review named in the byline is not verified here; nothing in this entry rests on it.
How this entry was checked and changed
Why this level

regraded 2026-09-27 from A: parallel RCT with n=17, no significant between-group difference

Content correction 2026-09-27
"Across multiple RCTs (8-12 weeks) HRV-guided groups showed equal or better improvements, total load often smaller, Z-score > −0.5 SD protocol, consumer apps, RCTs 4-12 weeks" -> composite claims not in the Javaloyes abstract (attributed to an unverified companion review); removed.
"Excuse avoidance", "structure-first for undertrained" -> not from the paper; removed.
Added the abstract's actual results: +5.1% PPO, +13.9% WVT2, +7.3% 40-min TT in the HRV group; no significant improvement in the traditional group; no significant between-group difference; MBI likely/possibly beneficial.
Level A -> B (parallel RCT, n=17); Tier "mixed→Tier 4-5 (Elite)" -> Tier 2-3 (well-trained cyclists); Sport "general" -> cycling.