- Functional overreaching, the dip a hard HYROX block can produce, is a temporary performance drop that improves after rest within days to weeks, in the European College of Sport Science terms used by Kreher and Schwartz's 2012 review.
- A HYROX training log for spotting overreaching can run on three lines: effort rating times minutes per session, one repeat session done identically, and a daily check against your own normal.
- When the repeat session in a HYROX training log slips at two weekly reviews in a row and motivation is down, race simulations and compromised running go first, as the two costliest session types in RoxTribe's training schedule guide.
- Resting heart rate and heart rate variability (HRV) are at most a tie-breaker in a HYROX training log, because Kreher and Schwartz's 2012 review reports they give inconsistent results and do not separate overreaching from overtraining syndrome.
- Kreher and Schwartz's 2012 review notes that some diagnose overtraining syndrome when regaining previous performance takes more than 14 to 21 days of rest, so a HYROX athlete at that point needs a doctor, not a new plan.
A list of overtraining signs tells you that you are tired, not which HYROX sessions to change this week. The standard HYROX format asks for 8 km of running and 8 stations, so a training week carries two kinds of fatigue. The HYROX training schedule guide sets out what each session type costs.
The short version: rate every session, keep one repeat session, and read the log weekly. The table below turns what the log shows into this week's changes, and the notes under it name the source behind each row. It covers a training block; post-race recovery has its own HYROX recovery guide, and the HYROX training guide holds the wider picture.
Overreaching and HYROX overtraining: where hard training stops paying
Kreher and Schwartz's 2012 review in Sports Health uses three European College of Sport Science terms. Functional overreaching is a temporary performance dip from increased training that improves after rest, lasting days to weeks, with a positive outcome. Non-functional overreaching is a longer dip from intense training, still fully recovered after rest but with added psychological or hormonal symptoms, lasting weeks to months. They describe overtraining syndrome as resembling extreme non-functional overreaching, with a dip of more than 2 months, more severe symptoms and an extra stressor no other disease explains.
That is why a log beats a checklist. The review says the two costly categories are told apart by time to recovery, not necessarily by the degree or type of symptoms, and often only after complete rest. No single bad day settles it.
For scale, the review says overtraining syndrome appears extremely rare, while one study it cites found a lifetime prevalence of non-functional overreaching of about 60% in elite runners and 33% in non-elite female runners. Those were runners, not HYROX racers. Treat the figures as a hint that the middle category is far from rare, rather than as your odds.
Overreaching on purpose is how a build works; the job is catching the slide into the costly kind. Kreher and Schwartz write that watching training load, performance and mood questionnaires can help interrupt it, and describe a study in which burnout among collegiate swimmers fell from 10% to zero when training load was adjusted in response to a mood questionnaire.
What goes in a HYROX training log
The Hospital for Special Surgery (HSS) advises keeping a training log of your well-being and how much you exercise, Cleveland Clinic says a workout journal can help once you are back to full training, and the International Olympic Committee (IOC) consensus on load and illness lists training diaries and questionnaires among the ways to monitor for overtraining syndrome. This log has three lines and two extras.
- Effort times minutes, every session. The session-RPE method, proposed by Foster and colleagues in 2001, rates the whole session from 0 to 10 (0 rest, 2 easy, 5 hard, 7 very hard, 10 maximal) and multiplies by the minutes. Worked example: a 50-minute compromised-running session rated 7 scores 350, and a 40-minute easy aerobic run rated 2 scores 80. In Haddad and colleagues' 2017 review, 36 studies that tested its validity and reliability confirmed both, and the authors say it could be used as a stand-alone method, though some add heart rate.
- One repeat session, done identically. Same route or set and intended effort, logged as a time and a rating; the timed easy run in the HYROX 12-week plan's week 1 baseline is one example. Saw, Main and Gastin's 2016 systematic review calls performance the ultimate indicator but impractical to test daily, and Kreher and Schwartz list a higher rating for a given workload among the initial signs of overreaching.
- A daily check against your own normal. Rate fatigue, motivation to train, soreness and niggles, how outside stress is affecting you, and general health as worse than normal, normal or better than normal. Saw and colleagues' review of 56 studies found self-reported measures reflected training load more sensitively and consistently than objective ones, and it supports daily self-rating against normal, which spares you a long baseline.
- Notes that are not training load: illness days, nights of broken sleep, stretches of work, family or travel stress, and, if you track them, body weight and menstrual cycle changes. Row 3 of the table reads the sleep and stress notes; the section on patterns outside the training plan reads the rest.
- Optional: a morning resting heart rate or HRV reading, as a tie-breaker only. Kreher and Schwartz report these neither show consistent results nor separate the three categories, and Saw and colleagues found subjective and objective measures generally did not correlate.
Rate daily, read weekly. One flat session means little: a case study that Kreher and Schwartz cite suggests fatigue is a normal experience for athletes, while falling vigour can be viewed as maladaptive.
What the last few weeks call for this week
At each weekly review, find the lowest row your log matches. The rows run from the lightest change to the heaviest, and each one already includes the cuts of every row above it. A session a row does not mention stays as planned, and if no row matches, keep the plan and look again next week. Masters racers have an earlier, age-specific trigger in the HYROX masters training guide, which moves a hard session when two of its weekly signals turn at once.
| Row | What your log shows | Change this week | Keep this week | Next check, and where each result leads |
|---|---|---|---|---|
| 1 | A planned build week: sessions feel harder, but the repeat session holds its time and rating, motivation is normal, and nothing has been added to the plan | Nothing. Add no session to test yourself | Every planned session, including the plan's next deload week | Next weekly review. Repeat session still holding: carry on. Slower or rated harder: match again from row 2 |
| 2 | After a slow race simulation or benchmark you added a session, and your next repeat session was no faster | Remove every session you added. Run the long run in place of any race simulation | The repeat session as usual, and every other planned session | Next weekly review. Repeat session back to its usual time and rating: return to the plan. Not back: row 4 |
| 3 | Broken sleep or work, family or travel stress in your notes, with sessions rated harder while training has stayed the same | Remove any session you added and drop compromised running. Shorten the long run and run it in place of any race simulation. Lighten strength (station-focused) if it does not feel normal | The repeat session as usual, other easy aerobic runs, any hard run, and strength (station-focused) at the planned load if it still feels normal | Next weekly review. Stress eased, repeat session holding: return to the plan. Stress continuing, repeat session holding: another week here. Repeat session slower or rated harder: row 4 |
| 4 | The repeat session slower, or the same time rated harder, at two weekly reviews in a row with motivation worse than normal; or not back after a week on row 2 or 3 | Remove any session you added and drop compromised running. Shorten the long run and run it in place of any race simulation. Run any hard run as an easy aerobic run. Cut strength (station-focused) to one session, lighter than planned. Shorten other easy aerobic runs | The repeat session as usual | Next weekly review. Repeat session back to its usual time and rating, daily checks normal: bring sessions back in the return order further down. Anything else: row 5 |
| 5 | Hard sessions you used to finish falling apart in the back half at two or more weekly reviews, alongside harder ratings or worse daily checks; or not cleared after a week on row 4 (repeat session back and daily checks normal) | Remove any session you added and drop compromised running. Shorten the long run and run it in place of any race simulation. Run any hard run as an easy aerobic run. Replace strength (station-focused) with short station technique work. Shorten other easy aerobic runs | The repeat session as usual | Next weekly review. Repeat session back to its usual time and rating, daily checks normal: bring sessions back in the return order further down. Anything else: stay here until two weeks have passed since you started row 4 or 5, then row 6 |
| 6 | Two weeks into rest, or into rows 4 and 5, without clearing (repeat session back and daily checks normal); or low mood most days, in training and out of it | Stop structured training of every kind and read the doctor section below | Easy movement you enjoy, if a doctor agrees | A doctor's assessment. Once a doctor agrees, re-run the repeat session; hard training restarts only when it is back, in the return order further down |
The rows and their order are RoxTribe's coaching judgement, and each rests on a sourced line. Row 1 rests on the case study cited above: harder sessions with motivation intact call for no change. A reflex two sources describe sits behind row 2: Kreher and Schwartz note underperformance is often met with more volume and intensity, and HSS says many athletes read poor performance as a signal to train harder. Row 3 draws on Kreher and Schwartz's potential triggers, which include sleep disturbances and personal and occupational stressors, and on the IOC consensus, which says an athlete reporting high daily hassle or stress could likely benefit from reducing the training load for a period.
Behind row 4 sit two lines from Kreher and Schwartz: a higher rating for a given workload is one of the initial signs of overreaching, and the case study suggests falling vigour may be more specific to overreaching than rising fatigue. Row 5 cuts harder because they list failing to finish a session you started, or losing a finishing kick, among history clues that raise suspicion of non-functional overreaching or overtraining syndrome rather than other disease. One late fade in one session is a question for the HYROX pacing guide instead. For row 6, Kreher and Schwartz note that some diagnose overtraining syndrome once regaining previous performance needs more than 14 to 21 days of rest. Acting at two weeks, the low end of that range, and counting weeks on rows 4 and 5 as well as rest, is RoxTribe's judgement; the low-mood line is sourced further down.
The cuts follow the training schedule guide's recovery costs, and Cleveland Clinic's steps for cutting back in overtraining syndrome also start by stopping high-intensity training. The table picks sessions. It does not tell you what you have.
Why simulations and compromised running go first
The standard HYROX format is eight rounds, each a 1 km run followed by one functional workout station, so a full simulation stacks running fatigue and station fatigue into one session. The training schedule guide's cost table rates compromised running the highest-cost session type and race simulation very high, the hard run high in central fatigue, strength high in local leg fatigue, and the easy aerobic run low. Under fatigue, cut from the top of that ranking.
That guide also has a cut order for weeks when you lose days, and in some of those weeks it protects compromised running. The two orders answer different shortages: when time is short, the question is which session earns its slot; when recovery is short, the most expensive sessions go first.
The easy runs stay, shortened, for the reason that guide gives: easy running does much of the recovery work, so when tired, shorten it rather than turn it into a rest day. The lighter strength session in row 4 is RoxTribe's reading of Kreher and Schwartz's note that rest treats non-functional overreaching and overtraining syndrome, though some propose relative rest instead.
Then there is the simulation trap. The HYROX simulation workout guide notes that a full simulation run within two weeks of the last one tells you more about how you have recovered than about how fit you are, and a slipping block puts any simulation in a similar position. So no row answers a slow simulation with another.
An illustrative month in the log
An illustrative Open racer, not data, on the training schedule guide's four-day week: strength on Tuesday, compromised running on Thursday, an easy aerobic run on Saturday and the long run on Sunday, with a race simulation replacing the long run in some weeks. The Saturday run, over a fixed route, is the repeat session.
- Week A, a planned build. Sessions felt harder, but the Saturday run held its time and rating and the athlete was keen. Row 1: no change.
- Week B. The Saturday run held its time but was rated harder, motivation read worse than normal on several days, and Sunday's race simulation was slower than the last. Straight after that simulation, and before the review, the athlete added a second compromised-running session to the coming week, on Wednesday, the active-recovery day. One review is not two in a row and the next repeat run had not happened, so no row matched.
- Week C. The Saturday run came in slower at its usual rating, and motivation was worse than normal most days. Rows 2 and 4 both match, and row 4 is the lower: Week D loses the Wednesday addition and compromised running, keeps one lighter strength session and the Saturday run, and shortens the long run.
- Week D. The Saturday run is back to Week A's time at Week A's rating and motivation is normal, so sessions return in the order under "The order the sessions come back in". Had it still been slower, the next review would have moved the athlete to row 5.
Patterns that belong with a doctor, not a training plan
A log can tell you when to train less, not why you are underperforming. If one of these fits, book an appointment before changing anything else.
- The repeat session has not come back two weeks into rest, or into the heavier cuts in rows 4 and 5. Kreher and Schwartz note that some diagnose overtraining syndrome when a return to previous performance needs more than 14 to 21 days of rest. They describe the diagnosis as clinical, from history: performance down despite weeks to months of recovery, disturbed mood, and no other cause, such as asthma, thyroid disease, iron deficiency with or without anaemia, infection, or malnutrition from eating disorders or coeliac disease. Cleveland Clinic says no single test confirms it; the review says no specific, validated blood markers exist.
- Illness that keeps coming back, or fever or whole-body symptoms. The IOC consensus associates high absolute training loads with a higher risk of illness in recreational and subelite athletes, says acute infective illness can raise the risk of serious medical complications during strenuous exercise, and notes that early fatigue, aches, headache and fever may signal illness or overreaching. Saw and colleagues note lab tests can detect recurrent infection and iron deficiency. The training schedule guide covers the first week back after an illness.
- Unplanned weight loss, irregular or missed periods, or stress fractures that keep happening. Cleveland Clinic says relative energy deficiency in sport (RED-S) can happen when you burn more calories exercising than you take in, and lists these among its symptoms alongside fatigue, a performance drop and slower recovery. It advises seeing a provider if performance is dipping or you have symptoms, especially if managing what you eat feels hard, and says a provider may suggest working with a registered dietitian. That overlap with overreaching is why no deload week or table row answers it. The HYROX nutrition guide covers fuelling basics.
- Low mood most days, no enjoyment left, or training that feels compulsive. Kreher and Schwartz write that most agree psychological distress is required to diagnose overtraining syndrome. Cleveland Clinic notes a provider may suggest a mental health specialist, and HSS suggests talking to someone if you feel obsessed with training, exercise through injury or pain, or feel guilty after a day without vigorous exercise.
- Pain in one place that is getting worse or changing how you move. This one is not a fatigue pattern, and Cleveland Clinic advises against ignoring minor symptoms or injuries. After a race, the HYROX recovery guide lists the urgent symptoms.
HSS advises talking with your coach, athletic trainer or doctor about overtraining symptoms, and says cutting back may be needed even if it means forgoing an upcoming competition. A race date is not a reason to wait. RoxTribe publishes training information, not medical advice, and nothing on this page diagnoses anything.
The order the sessions come back in
Kreher and Schwartz's treatment advice is to build volume back before intensity, and HSS gives renewed interest and the ability to train hard with normal responses as signs you are likely ready for full training. The log confirms it when the repeat session is back at its old time and rating and the daily checks read normal. Length comes back first, then load and intensity:
- Easy aerobic runs, back to full length
- The long run, back to full length
- Strength (station-focused), back to the planned load
- Any hard run
- Compromised running
- Race simulation, last
This order is for leaving rows 4, 5 and 6; rows 2 and 3 go straight back to the plan. Bring sessions back one at a time, as the HYROX running plan changes one variable at a time. If the race now falls inside the final week, the HYROX taper week guide takes over; the 12-week plan warns that squeezing missed work into the taper costs you on race day.
The Running Channel walks through overreaching and overtraining
The Running Channel's presenters walk through functional overreaching, non-functional overreaching and overtraining syndrome. One describes fatigue that "went way beyond just my legs". Their recovery plan is more conservative than rows 4 and 5 here: step one removes all structured training, hard workouts and long runs included.
Frequently asked questions about HYROX overtraining
Am I overtraining for HYROX, or just tired?
One tired week cannot tell you. In a case study Kreher and Schwartz's review cites, tiredness on its own is suggested to be ordinary for athletes, and falling vigour may be the more telling sign. So watch two things across weekly reviews: whether your repeat session holds its time and rating, and whether your motivation stays normal.
What separates overreaching from overtraining?
Recovery time. In the European College of Sport Science terms that Kreher and Schwartz use, functional overreaching clears in days to weeks and ends with better performance, non-functional overreaching takes weeks to months, and overtraining syndrome takes months. The review adds that the last two can often be told apart only in retrospect, after rest.
Do resting heart rate and HRV show overtraining?
Not reliably. Kreher and Schwartz's review reports that resting heart rate, maximal heart rate and HRV give inconsistent results and cannot tell the three categories apart. Saw and colleagues' systematic review found self-reported measures more sensitive to training load than objective ones. A device reading can break a tie in your log, not settle it.
Is another simulation the answer to a slow one?
Usually not. Kreher and Schwartz observe that underperformance is often met with more training volume and intensity. The HYROX simulation guide adds that a second full simulation within two weeks of the last shows how well you have recovered more than how fit you are. Remove anything you added, then recheck your repeat session first.
Will a deload week fix overtraining?
A deload week suits functional overreaching, which by definition improves after rest. It does not fix overtraining syndrome, which Kreher and Schwartz describe as lasting months. If your repeat session is back after the deload, carry on with the plan. If not, cut compromised running and race simulations first instead of repeating the deload.
Does work stress count towards HYROX overtraining?
It can. Personal and occupational stress sits on Kreher and Schwartz's list of potential triggers, alongside disturbed sleep. The IOC's 2016 consensus on load and illness suggests an athlete under heavy daily hassle or stress may benefit from training lighter for a while. Note outside stress daily, so a hard week at work shows up beside your sessions.
Is overtraining a risk for newer HYROX racers?
It can happen, though Kreher and Schwartz describe the full syndrome as appearing extremely rare. Cleveland Clinic says anyone physically active can develop it, and names suddenly doubling how far you go on regular runs, without building endurance first, as one route in. The HYROX beginner plan is an on-ramp for building that base.
Should I still start a HYROX if my log slips in the final weeks?
It depends on what your log shows. A slipping repeat session in the last few weeks calls for dropping compromised running and any simulation, then the taper as planned rather than a squeezed one. If weeks of those cuts have not brought the repeat session back, HSS notes that recovery can mean forgoing an upcoming competition.
Build the week this log protects, then read the log once a week. If a pattern from the doctor section fits, that appointment comes before any other change.
The HYROX 12-week planReferences
- Kreher JB, Schwartz JB. "Overtraining Syndrome: A Practical Guide." Sports Health, 2012. Read in full.
- Saw AE, Main LC, Gastin PB. "Monitoring the athlete training response: subjective self-reported measures trump commonly used objective measures: a systematic review." British Journal of Sports Medicine, 2016. Abstract, introduction and discussion read.
- Haddad M, et al. "Session-RPE Method for Training Load Monitoring: Validity, Ecological Usefulness, and Influencing Factors." Frontiers in Neuroscience, 2017.
- Schwellnus M, et al. "How much is too much? (Part 2) International Olympic Committee consensus statement on load in sport and risk of illness." British Journal of Sports Medicine, 2016.
- Hospital for Special Surgery, "Overtraining: What It Is, Symptoms, and Recovery," 2021.
- Cleveland Clinic, "Overtraining Syndrome," last updated 2024.
- Cleveland Clinic, "Relative Energy Deficiency in Sport (RED-S)," last updated 2026.