The Science Your Cycle Phase Guides The Lab @thesyncbrand
Cycle-synced training science

Your cycle
isn't the
problem.
Ignoring it is.

The science of exercise isn't built for women.
It's time that changed.

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The research
wasn't built
for you.

"Only 6% of sports science research focuses exclusively on women."

The rest was built on male bodies, and applied to ours.

The training plans you've followed, the fuelling strategies you've been given, the recovery windows you've been prescribed. All built on male biology.

Not just suboptimal. For many women, actively harmful. Disrupting the very hormones that help you perform.

As Dr. Stacey Sims puts it: women aren't small men. SYNC exists to give you the science that was always meant for you.

Sources: Sports & Exercise Science journal analysis, 2022; Costello et al., 2014; Dr. Stacey Sims, Roar, 2016
Cycle-synced training
Hormonal science
Evidence-based
94%
without us

If men had periods,
sports science would
look very different.

(and we wouldn't hear the end of it...)

So we built SYNC, because understanding your cycle isn't a wellness trend, it's a necessity.

Four phases.
Four versions of you.

Your cycle can boost your performance.
You just need to know how to use it.

1
Days 1 to 5
Menstrual
Train: Rest & restore

Oestrogen and progesterone are at their lowest. Inflammation is naturally higher. Gentle movement and prioritising sleep are your best performance tools right now.

2
Days 6 to 13
Follicular
Train: Hit new PBs

Rising oestrogen improves muscle recovery and pain tolerance. Strength and power are peaking. This is your window for max effort.

3
Days 14 to 17
Ovulatory
Train: Race & compete

Peak energy. Peak coordination. Slightly higher ligament injury risk, so warm up well. The best time to race, compete, or go after something that matters.

4
Days 18 to 28
Luteal
Train: Steady & strategic

Core temp rises. Perceived effort increases. Fuel more, rest more. Working with progesterone is not weakness. It's intelligence.

In the wise words of Dr. Stacey Sims, 'Women aren't small men.' It's time science caught up.
01

Science-first

Everything we share is grounded in peer-reviewed research on female physiology. No bro-science. No watered-down wellness content.

02

Cycle-synced

Your training, nutrition, and recovery advice shifts with your hormones. Because the same session hits differently on day 5 vs day 20.

03

Real talk

We're not here to sanitise this. Periods, hormones, cycle phases. The most powerful performance tool you have.

Your complete
phase-by-phase guide.

Mood, energy, training, nutrition, supplements and recovery mapped across all four phases of your cycle.

Phase 01

Menstrual

Days 1 to 5
Low estrogen, low progesterone, low testosterone

Mood and Energy

All three hormones are at their lowest. Expect:

  • Low energy and fatigue
  • Increased sensitivity and introversion
  • Cramps and physical discomfort
  • Desire to withdraw and rest
  • Potential brain fog and low motivation

Training

This is your rest and recovery window:

  • Light yoga, stretching, mobility work
  • Walking or gentle swimming
  • Reduce training intensity by 40 to 60%
  • Skip high-impact or HIIT sessions
  • Focus on breathwork and nervous system regulation

Nutrition and Supplements

Replace what you're losing and fight inflammation:

  • Iron-rich foods like red meat, spinach and lentils (you're losing iron daily)
  • Vitamin C to pair with iron for absorption
  • Magnesium to ease cramps and support sleep
  • Anti-inflammatory foods like turmeric, ginger and fatty fish
  • Increase calories slightly as your body needs fuel to repair

Recovery and Sleep

  • Prioritise 8+ hours of sleep
  • Muscle repair is impaired so avoid heavy eccentric work
  • Hot baths or heat packs help with cramp relief
  • Body temperature is lower so you may actually sleep better

What to Expect

  • Cramps (prostaglandin-driven)
  • Loss of iron through menstrual blood
  • Limited motivation for intense exercise
  • Heightened emotional sensitivity
  • Potential headaches and bloating

SYNC Tip

This is not the time to push through. Rest is productive. The fitter you are, the more you need intentional deloads. Think of menstruation as your body's built-in recovery week. Use it wisely and you'll come back stronger in the follicular phase.

Phase 02

Follicular

Days 6 to 13
Rising estrogen, building testosterone, low progesterone

Mood and Energy

  • Clear mind, sharp focus
  • High energy and motivation
  • Good mood and optimism
  • Feeling social and outgoing
  • Calm, confident baseline

Training

This is your performance window. Go hard:

  • Lift heavy as strength peaks here
  • Chase PBs and progressive overload
  • HIIT, sprints and plyometrics all respond well
  • Higher training volume tolerated
  • Ideal time to learn new skills or movements

Nutrition and Supplements

  • Lean protein to support muscle protein synthesis
  • Creatine at 5g daily for strength and cognition
  • EAAs at 12g around training for recovery
  • Complex carbs to fuel high-intensity work
  • Estrogen supports insulin sensitivity so carbs are used efficiently

Recovery and Sleep

  • Recovery is efficient as estrogen is anti-inflammatory
  • Good sleep quality
  • Faster muscle repair between sessions
  • Can handle back-to-back training days

What to Expect

  • Strong and resilient
  • High pain tolerance
  • Peak motivation to train
  • Good appetite regulation
  • Feeling like your best self

SYNC Tip

This is your green light window. The combination of rising estrogen and testosterone makes this the optimal time for strength gains, skill acquisition and pushing limits. If you're going to test a 1RM or enter a competition, aim for late follicular or early ovulatory.

Phase 03

Ovulatory

Days 14 to 17
Estrogen peaks, testosterone peaks, LH surge

Mood and Energy

  • Peak energy, this is your absolute high point
  • Confident and assertive
  • Sharp mentally, creative and articulate
  • Highly social, high libido
  • Motivated and driven

Training

Peak performance window. Compete and push limits:

  • Race day, competition, time trials
  • Sprint intervals, explosive work
  • Maximal lifts and power output
  • Peak recovery so double sessions are tolerated
  • Note: ligament laxity increases so warm up thoroughly

Nutrition and Supplements

  • High protein to support peak training demands
  • Creatine and EAAs with continued daily dosing
  • Hydration as estrogen affects fluid balance
  • Cruciferous veg like broccoli and kale to support estrogen metabolism
  • Appetite may naturally decrease so eat to fuel performance, not appetite

Recovery and Sleep

  • Peak recovery capacity
  • Fast muscle repair
  • Efficient sleep (though some may feel too energised)
  • Body temperature begins to rise post-ovulation

What to Expect

  • Feeling unstoppable
  • High confidence and charisma
  • Peak physical performance
  • Increased ligament laxity (ACL injury risk rises)
  • This phase is short so make the most of it

SYNC Tip

Peak estrogen and testosterone make this a short but powerful window. Schedule your biggest training sessions, races or presentations here. But be mindful of joint stability as studies show ACL injury risk is 3 to 6x higher around ovulation due to estrogen's effect on ligament laxity. Warm up properly and focus on controlled landings.

Phase 04

Luteal

Days 18 to 28
High progesterone, falling estrogen, rising then crashing hormones

Mood and Energy

  • Fatigue and lower energy (especially late luteal)
  • Irritability, anxiety and mood swings
  • Brain fog and reduced concentration
  • High stress and emotional reactivity
  • Cravings, especially sugar and carbs
  • Low motivation, desire to withdraw

Training

Pull back intensity and focus on steady, strategic work:

  • Moderate-intensity steady state (zone 2 cardio)
  • Lighter weights, higher reps
  • Pilates, swimming, cycling
  • Avoid maximal lifts and heavy HIIT
  • Be kind to yourself. This is not weakness, it's biology.

Nutrition and Supplements

  • Magnesium glycinate at 400mg for cramps, sleep and mood
  • Curcumin with 95% curcuminoids as a potent anti-inflammatory
  • Ginger root to fight nausea and inflammation
  • Complex carbs as progesterone increases metabolic rate
  • Calcium and Vitamin D shown to reduce PMS severity
  • Increase calories by 200 to 300 per day as your body burns more

Recovery and Sleep

  • Poor recovery as progesterone is catabolic
  • More rest required between sessions
  • Core body temperature rises which disrupts sleep
  • Sleep quality declines, especially days 22 to 28
  • Cool sleeping environment helps (18 degrees ideal)

What to Expect

  • Increased hunger and cravings
  • Water retention and bloating
  • Breast tenderness
  • Higher inflammation markers
  • Reduced pain tolerance
  • Emotional volatility peaks days 22 to 28

SYNC Tip

The luteal phase is where most women feel they're "failing" at fitness. You're not. Your progesterone is peaking, your metabolic rate is higher, and your body is prioritising survival over performance. Eat more, train gentler and sleep longer. This is where the SYNC SHIELD Moon Milk formula was designed to help with magnesium, curcumin and ginger to fight inflammation and support calm.

Late Luteal: Days 22 to 28

The final week before your period is when PMS symptoms peak. Both estrogen and progesterone crash simultaneously, triggering the strongest mood, energy and physical shifts of the entire cycle.

Read: Why the Last Week Hits Different
  • Inflammation peaks so anti-inflammatory nutrition is critical
  • Serotonin drops so mood support through diet and sleep matters
  • Core temperature rises and sleep quality suffers most here
  • Metabolic rate is 200 to 300 cals higher so eat accordingly
  • Rest is not lazy. It's the smartest thing you can do.

The science,
without the fluff.

Short, sourced, and actually applicable to your body.

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