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Built for female athletes

Your body isn't
a liability.
It's your edge.

The first wellness app built around the female athletic cycle. Train smarter, recover faster, and stay injury-free — by working with your body, not against it.

→ Open the App See the science ↓
A
R
S
Built for youth female soccer players — ages 13–19
● Your Phase Today
Follicular
Day 8 · Rising energy
● High energy ● Build strength ● Low injury risk
NUTRITION · YOUR PHASE
This is your window to build strength — fuel it
Your muscles are primed to grow. Hit your protein targets today.
INJURY PREVENTION
Your injury risk is low — push confidently
Ligament laxity is stable. Best week to increase training load.
✓
✓
✓
14●
Prediction accuracy
89%
after 3 cycles
Injury risk
2–8×
higher during ovulation — if you don't know
89%
of female athletes say their cycle affects performance
2–8×
higher ACL injury risk during ovulation phase
0%
of youth clubs currently monitor menstrual cycle in training
2023
IOC published guidelines calling for this at every level
The Science

Four phases.
Four completely
different athletes.

Your hormones change everything — energy, strength, injury risk, mood, and recovery. Addy Health tracks where you are in your cycle and gives you phase-specific guidance every single day.

Phase 1 · Menstrual
Rest is training, not giving up
The elite athletes who perform best use this phase for mental sharpness and tactical review — not maximum effort.
Phase 2 · Follicular
Your power window is open
Rising estrogen means muscles respond 15–20% faster to training. This is the week to push hardest and learn new skills.
Phase 3 · Ovulation
Peak output, elevated risk
ACL injury risk is 2–8× higher right now due to ligament laxity. A longer warm-up changes everything this week.
Phase 4 · Luteal
Skill over intensity
Progesterone raises perceived effort. Elite coaches shift to tactics and technique this phase — so should you.
What Addy Health Does

Everything your body
needs you to know.

●
Phase Predictions
Enter your last period date and cycle length. Addy Health maps your next three cycles and tells you exactly which phase you're in every day — no guessing.
●
Phase Nutrition Guide
Iron and omega-3s during menstrual phase. Protein timing during follicular. Hydration during ovulation. Magnesium during luteal. The right fuel, every week.
●
Sleep Guidance
Progesterone disrupts REM sleep in your luteal phase. Estrogen improves it in follicular. We tell you what's happening and exactly how to respond.
●
Injury Prevention Alerts
3 days before your ovulation window opens, the app flags elevated ligament laxity and gives your warm-up a specific protocol. Built around the IOC 2023 guidelines.
●
10-Second Daily Log
Mood, energy, sleep hours, training, nutrition, pain location. Six visual questions that auto-advance on tap. Takes less time than tying your boots.
●
Streak & Squad
Daily streak counter with celebrations at 7, 14, 21, and 30 days. Squad status shows which teammates have logged today — the single best retention mechanic we've found.
Our Story

"What if she had known which phase she was in the day she got hurt?"

The question that built Addy Health Addyson was 14, playing ECNL elite soccer, when a syndesmosis ankle injury required surgery and ended her season. Research revealed that ligament injury risk is 2–8× higher during ovulation due to hormonal laxity. She was in that window. The data existed. The tool didn't. Addy Health is her answer.

2023
IOC Consensus StatementCalls for menstrual cycle monitoring at all levels of female athlete programs. Zero youth clubs currently do this.
2–8×
Higher ligament injury risk during ovulationPeak estrogen increases ankle and knee laxity — the exact window Addyson was injured in.
13–19
The age group most at riskAdolescent female athletes have the highest rates of ligament injury — and the least access to cycle-informed training.
The Dropout Problem

Girls don't quit soccer.
They quit a sport that
stopped making sense
for their body.

Between 13 and 17, girls leave organised sport at dramatically higher rates than boys. Puberty is at the centre of it — and nobody is explaining what's happening.

2×
Girls drop out of sports at twice the rate of boys by age 14Through 25+ years of research, the Women's Sports Foundation identifies this gap opening precisely at puberty — when bodies start changing and nobody explains why. Women's Sports Foundation, Keeping Girls in the Game, 2020
−51%
Female attrition rate from 8th to 12th gradeGirls lose more than half their participation between middle and high school — compared to −31% for boys over the same period. U.S. Soccer Foundation, citing Women's Sports Foundation data

The Women's Sports Foundation identifies body image and puberty as significant factors — girls report feeling like their body is working against them. Performance dips at the same point each month. Effort spikes for no obvious reason. Without an explanation, the only conclusion available is: I'm not cut out for this anymore.

What's happening is physiological and measurable. Progesterone in the luteal phase raises perceived exertion — the same training session genuinely feels harder. Iron loss during menstruation reduces energy and reaction time within days. Body changes during puberty temporarily alter balance and coordination, making skills that felt automatic suddenly unreliable.

Research across 33 countries found that menstrual stigma and lack of education are consistent barriers to physical activity for adolescent girls — and that fewer than one in four female athletes rate their own knowledge of how their cycle affects their body as good or very good. Most coaches rate even lower.

Why effort feels harder some weeks
Why energy dips before a period
Why familiar skills suddenly feel off
Why injury risk spikes at the same point each month
Why some weeks feel unstoppable and others feel flat

None of this is weakness. It's physiology. And when a girl understands that — she stops quitting.

Wellness Guide

Real guidance for
every phase.

Every tip is backed by peer-reviewed research and written in a tone that feels like advice from a cool older sister who plays college soccer — not a doctor.

Nutrition
This is your window to build strength — fuel it
Estrogen is rising and your muscles are primed. Hit 1.6g of protein per kg of bodyweight today. Your body absorbs it better during this phase than any other.
Sleep
You're probably sleeping better right now
Rising estrogen improves REM sleep quality. This is the best sleep of your cycle — aim for 8–9 hours and use the natural quality boost your hormones are giving you.
Injury Prevention
Your injury risk is low — push confidently
Ligament laxity is stable and your neuromuscular coordination is at its best. ACL injury risk is lowest this phase. This is the week to increase load and try new skills.
Nutrition
Iron is your best friend right now
You're losing iron during your period and low iron causes that heavy, foggy feeling. Spinach, red meat, lentils, and dark chocolate — pair with Vitamin C to double absorption.
Sleep
Why sleep feels harder — and how to fix it
Progesterone is dropping and your body temperature is slightly higher. A cool room (18°C), a heat pack on your abdomen, and 300mg magnesium glycinate before bed makes a real difference.
Injury Prevention
Rest is training. Full stop.
Ligament laxity is actually lowest during menstruation — so injury risk is lower. But energy and pain tolerance are down. Modified training isn't weakness. Elite athletes plan this.
Nutrition
Hydration is your most important job today
Peak estrogen raises core body temperature and sweat rate. Dehydration compounds ligament vulnerability. Aim for 2.5–3L today. Add electrolytes before and during training.
Sleep
You might feel wired at night this week
The LH surge that triggers ovulation increases alertness and can delay sleep onset. Start your bedtime routine 30 minutes earlier. Reduce screens after 9pm. Chamomile tea helps.
Injury Prevention
Your highest risk window — here's the protocol
Peak estrogen increases ankle and knee laxity by 1.5–3mm. Add 10 minutes of proprioception work before training. Plant and cut with more knee bend. Ice ankles and knees after every session.
Nutrition
Carb cravings are real — your body has a reason
Progesterone raises your metabolic rate, which is why you feel hungrier. Complex carbs — oats, sweet potato, brown rice — satisfy cravings AND stabilise blood sugar. Don't restrict.
Sleep
Progesterone disrupts REM sleep — fight back
Magnesium glycinate 300mg before bed. Keep your room cool. Avoid intense training within 3 hours of sleep. Limit caffeine after 1pm — you're more sensitive to it now.
Injury Prevention
Skill over intensity this week
Progesterone increases perceived effort for the same workload. Shift to technique, tactics, and mental game. Reduce impact volume by 10–20%. Come out of it sharper, not depleted.
● International Olympic Committee — 2023

"Menstrual cycle monitoring should be implemented at all levels of female athlete programs."

IOC REDs Consensus Statement, British Journal of Sports Medicine, September 2023. Addy Health is the first tool built to make this recommendation actionable for youth athletes.

Ready to train
in sync?

Open the app, enter your cycle start date, and get your first personalised phase guide in under 2 minutes.

→ Open Addy Health

Free to use · No download required · Works on any phone