How the Menstrual Cycle Affects Women in Sports
Updated: Oct 16
By Lianne Everett, Registered Chiropractor & Sports Massage Therapist at Bristol Chiropractic Sports and Family Clinic | Updated 20 October 2026 | 10 min read
✔ Evidence-Based ✔ Written by a Registered Chiropractor ✔ GCC Regulated
In a nutshell: For female athletes, the menstrual cycle is more than a monthly occurrence — hormonal fluctuations genuinely affect the body, and many athletes notice real changes in energy, strength, and recovery across the month.
But the research is more cautious than a lot of popular advice suggests: large reviews consistently find that objective performance effects are small, inconsistent, or "trivial" at a group level, even though individual symptoms are very real.
This post explains what's actually been shown, what's still genuinely uncertain, and how to use that information sensibly rather than following a rigid "phase-based" training plan.
Contents
1. Why This Topic Matters
Despite its significant impact on half the athletic population, menstruation remains an under-discussed topic in sport. I see this regularly through my work with a rugby medical team: athletes training and competing hard every week, often without much open conversation about how their cycle affects their body, or whether what they've read online actually holds up.
It's worth being upfront about something important: a lot of popular content on this topic overstates how clear-cut the science is. You'll often see confident claims that strength "peaks" in one phase and "crashes" in another. When you look at the actual research — systematic reviews, meta-analyses, and recent consensus statements from major sporting bodies — the picture is far less tidy. That doesn't mean the menstrual cycle doesn't matter. It means the honest answer is more nuanced, and more useful, than a simple phase-by-phase formula.
2. The Four Phases, and What the Evidence Actually Shows
The menstrual cycle typically lasts around 28 days (though this varies considerably between individuals) and is generally described in four phases.
Menstrual phase (roughly days 1–5). Hormone levels drop and the uterine lining sheds. Many athletes report fatigue, cramps, and a sense of reduced capacity during this phase. A narrative review of athlete-reported experience found that perceived performance is consistently rated as worse during the early follicular (which overlaps with menstruation) and late luteal phases — but when researchers measured actual strength, power, or endurance output rather than asking how athletes felt, they did not find consistent effects. In other words, how you feel and what your body can actually do don't always move together, and both are worth taking seriously.
Follicular phase (roughly days 6–14). Oestrogen rises steadily through this phase. It's commonly claimed that strength and performance "peak" here due to oestrogen's effects on muscle and recovery. A large network meta-analysis pooling data across dozens of studies did find a statistically detectable dip in performance during the early follicular phase compared with other phases — but the researchers themselves described the effect size as trivial, and concluded it's unlikely to be meaningful for most athletes' day-to-day training decisions.
Ovulation (around day 14). Oestrogen peaks here, alongside a smaller rise in testosterone, which some athletes associate with feeling stronger or more motivated. This phase is also where ligament laxity — including in the knee — tends to increase, which is covered in more detail below.
Luteal phase (roughly days 15–28). Progesterone rises, which is where some of the clearest, most consistently replicated physiological changes occur. Multiple studies confirm that resting core body temperature increases by around 0.3–0.5°C during the luteal phase due to progesterone's thermogenic effect, and this elevated baseline can increase thermal strain during exercise, particularly in hot or humid conditions. This is one of the few menstrual-cycle effects with genuinely consistent evidence behind it — unlike the strength and power claims above, which are far less settled. Fatigue and reduced recovery capacity are also commonly reported in this phase, though as with the follicular phase, self-reported and objectively measured effects don't always align.
The bottom line: some hormonal effects (like the luteal-phase temperature rise) are well established. Others — particularly claims about strength or power "peaking" and "crashing" by phase — are much weaker than popular fitness content suggests. A 2025 review of the literature concluded that most research in this area remains limited by small sample sizes and inconsistent methodology, and that general, population-wide training rules based on cycle phase are not currently well supported by evidence.
3. The ACL Injury Question
This is one of the most searched — and most oversimplified — topics in this space, so it's worth addressing directly.
It's true that oestrogen can increase ligament laxity, and several studies have found that knee laxity measurably increases around ovulation when oestrogen peaks. It's also true that women are two to four times more likely to suffer ACL injuries than men, which has driven a lot of research interest in whether the cycle itself is a risk factor.
But here's where it gets more complicated than most articles let on: a systematic review of biomechanical and neuromuscular ACL injury risk markers found the evidence inconclusive as to whether any particular cycle phase increases injury risk. A separate 2022 systematic review concluded that, based on the current literature, a direct correlation between the menstrual cycle and ACL injury risk could not be established — despite the laxity changes being real. And a large meta-analysis of ACL injury data actually found the luteal phase, not ovulation, was the phase least associated with ACL injuries in studies that didn't use hormonal contraception.
What this means practically: increased knee laxity around ovulation is a genuine, measurable phenomenon. Whether that translates into meaningfully higher injury risk for an individual athlete is not something the current evidence can confirm. If you've had previous knee injuries or your coach or physio is monitoring your knee stability, it may still be sensible to pay closer attention around ovulation — but this should be framed as a precaution based on a plausible mechanism, not a settled fact.
4. Managing Training Around Your Cycle
Given how mixed the group-level evidence is, the most credible current guidance — including a 2025 UEFA consensus statement on menstrual cycle tracking in women's football, developed with input from leading researchers in this field — is to move away from rigid, cycle-phase-based training templates and toward an individualised, symptom-led approach instead.
Tracking, done well, is still worth doing. The UEFA consensus and similar guidance from World Rugby both note that while evidence linking cycle phase directly to performance or injury risk remains inconclusive, tracking still has real value: it helps identify menstrual irregularities early (which can be an important health marker in itself), helps you and your coach understand your personal symptom pattern, and supports better day-to-day communication about training load.
Adjust based on your actual symptoms, not a generic chart. If you consistently feel more fatigued or notice reduced capacity in your luteal or early follicular phase, it's entirely reasonable to factor that into your training — not because research says every athlete should, but because your own tracked data says you do.
Be especially mindful of heat. Given how consistent the evidence is on luteal-phase core temperature increases, this is one area where a genuine physiological adjustment makes sense: extra attention to hydration, cooling strategies, and pacing during hot-weather training or competition in the second half of your cycle.
Nutrition and hydration. Eating iron-rich foods, staying hydrated, and maintaining a balanced diet generally support recovery and help manage fatigue, regardless of cycle phase.
Recovery strategies. Prioritising sleep, active recovery, and stress management supports overall wellbeing and training capacity throughout the month.
Talk to your coaches and medical team. The strongest practical recommendation across the current research isn't a specific training formula — it's better communication. Athletes who feel able to discuss menstrual health openly with coaches and practitioners are better placed to get support tailored to their actual experience, not a generic assumption.
5. When to See a Doctor, Not Just a Trainer
Most of what's discussed above falls into the category of normal cycle variation. But some symptoms are worth raising with a GP rather than just adjusting your training plan around:
Periods that stop, become very irregular, or haven't started by age 16
Very heavy bleeding, or periods lasting significantly longer than usual
Severe pain that doesn't respond to normal pain relief or significantly limits daily activity
Signs that could indicate Relative Energy Deficiency in Sport (RED-S) — this includes a combination of low energy availability, menstrual irregularities, and reduced bone density, and is a recognised risk for athletes training at high volumes, particularly in endurance and aesthetic sports
Missed or irregular periods in an athlete should never simply be assumed to be "normal for someone who trains hard." It can be a genuine health marker that's worth investigating, not just a training inconvenience.
6. When a Chiropractor or Sports Massage Therapist Can Help
While the menstrual cycle itself is a medical topic best managed with your GP or a sports physician, there's a lot we can support alongside that. If you're dealing with lower back pain or pelvic discomfort that worsens around your period, joint stiffness or muscle tension linked to fatigue in the luteal phase, or you simply want structured support through a heavy training block, both chiropractic care and sports massage have a role to play.
A sports massage can help manage muscle tension and support recovery, particularly if you're training through a phase where you're feeling more fatigued than usual. Chiropractic care can help with joint restriction, postural strain, or pain patterns that flare around certain points in your cycle. And because I work within a rugby medical team as well as in clinic, I'm used to helping athletes build training and recovery plans that actually reflect what their training schedule and their body are telling them — not a generic template.
7. Frequently Asked Questions
Does my period really affect my sports performance? Many athletes report feeling it does, and perceived performance does tend to be rated lower during menstruation and the late luteal phase. However, objectively measured strength, power, and endurance don't show the same consistent pattern across most research — so the honest answer is "it's individual, and worth tracking for yourself."
Should I avoid training on my period? Not necessarily. There's no strong evidence that training during menstruation is harmful, and plenty of athletes train and compete successfully throughout their cycle, including at elite level. Light, symptom-appropriate exercise can also help some people feel better by increasing blood flow.
Is ovulation really a dangerous time for my knees? Ligament laxity does measurably increase around ovulation, but current evidence can't confirm this directly raises ACL injury risk. It's reasonable to be a little more cautious if you have a history of knee problems, but it's not a settled fact that ovulation itself causes injuries.
Should I use an app to track my cycle? Current sporting guidance generally supports tracking as a useful tool — mainly because it helps you spot your own patterns and flags irregularities early, not because it will tell you a universal formula for training.
What if my periods have stopped because of training? This is worth discussing with a GP rather than assuming it's a normal side effect of being an athlete. It can be linked to Relative Energy Deficiency in Sport and is worth investigating properly.
8. Want Support That Actually Fits Your Training? Let's Talk
If you're managing training, competition, and the day-to-day reality of your menstrual cycle, you don't have to figure it out alone — or follow a generic online formula that doesn't reflect your own experience. At Bristol Chiropractic Sports and Family Clinic, we support athletes with chiropractic care and sports massage tailored to how your body and training are actually responding.
📍 Located at 2 Kellaway Avenue, Westbury Park, Bristol BS6 7XR — serving patients across Westbury Park, Henleaze, Westbury-on-Trym, Redland, Bishopston, Horfield, Clifton, Cotham, and the surrounding area.
Book your assessment today → https://www.bristol-chiropractic.co.uk/online-booking
Or call us on 0117 9620100 to talk through your training and symptoms before you book.
9. About the Author
Lianne Everett is a Registered Chiropractor
Lianne is passionate about the intersection of sports and wellness, with a focus on optimising athletic performance and reducing injury risk. Her expertise extends beyond the treatment room — she plays an active role within a rugby medical team, providing care and support to injured athletes, which directly shapes her understanding of sports-related injury and recovery.
Driven by a commitment to helping athletes perform at their best, Lianne combines hands-on clinical knowledge with a genuine passion for sport — rugby especially — and ongoing professional learning to provide well-rounded care for people pursuing excellence in sport.
👉 Book online: https://www.bristol-chiropractic.co.uk/online-booking
10. References & Further Reading
Carmichael MA, Thomson RL, Moran LJ, Wycherley TP. The Impact of Menstrual Cycle Phase on Athletes' Performance: A Narrative Review. International Journal of Environmental Research and Public Health. 2021;18(4):1667. https://pmc.ncbi.nlm.nih.gov/articles/PMC7916245/
McNulty KL, et al. The Effects of Menstrual Cycle Phase on Exercise Performance in Eumenorrheic Women: A Systematic Review and Meta-Analysis. Sports Medicine. 2020;50:1813–1827. https://rgu-repository.worktribe.com/OutputFile/940995
Janse de Jonge XAK. Effects of the Menstrual Cycle on Exercise Performance. Sports Medicine. 2003;33(11):833–851. https://pubmed.ncbi.nlm.nih.gov/12959622/
On exercise thermoregulation in females: interaction of endogenous and exogenous ovarian hormones. PMC. https://pmc.ncbi.nlm.nih.gov/articles/PMC6312528
Effects of the menstrual cycle phase on anterior cruciate ligament neuromuscular and biomechanical injury risk surrogates in eumenorrheic and naturally menstruating women: A systematic review. PMC. https://pmc.ncbi.nlm.nih.gov/articles/PMC9879429/
Moriceau J, et al. The Influence of the Menstrual Cycle and Oral Contraceptives on Knee Laxity or Anterior Cruciate Ligament Injury Risk: A Systematic Review. Applied Sciences. 2022. https://doaj.org/article/56b737c5e1aa47bdbc80bc43b1d687c7
Herzberg SD, et al. The Effect of Menstrual Cycle and Contraceptives on ACL Injuries and Laxity: A Systematic Review and Meta-analysis. Orthopaedic Journal of Sports Medicine. 2017;5(7). https://rrmacademy.org/library/the-effect-of-menstrual-cycle-and-contraceptives-on-acl-injuries-and-laxity-a-sy-tsby1uin/
Verhagen E, et al. UEFA consensus statement on menstrual cycle tracking in women's football. BMJ Open Sport & Exercise Medicine. 2025;11(3). https://pmc.ncbi.nlm.nih.gov/articles/PMC12458775
World Rugby. The Menstrual Cycle: What Coaches Need to Know. https://passport.world.rugby/conditioning-for-rugby/advanced-conditioning-for-female-rugby-players/the-menstrual-cycle-what-coaches-need-to-know/summary/
Elite Sports Medicine. The Effects of Menstrual Cycle Phase on Elite Athlete Performance: A Critical and Systematic Review. PMC. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8170151/
sportscotland Institute of Sport. Fact sheet: RED-S (Relative Energy Deficiency in Sport). https://sportscotland.org.uk/performance/cutting-edge/archive/fact-sheet-red-s
This article is for general information and does not replace individual medical, chiropractic, or sports medicine advice. If your periods have stopped, become very irregular, or you're concerned about your menstrual health as an athlete, please see your GP.
