The Female Athlete Triad Dr Leon Creaney Sport & Exercise Medicine Physician BMedSci MBChB MRCP MRCGP FFSEM STH Grand Round

Female Athlete Triad refers to the relationship between chronically Low Energy Availability leading to menstrual dysfunction and low bone mineral density, seen most commonly in sports that emphasize low body weight. Low Energy Availability

Menstrual Problems

Low BMD

Basic Physiology

Energy Availability  The total remaining energy available for all

other metabolic processes after calories spent in physical activity (exercise/sport). Energy In (Food and Drink) Minus  Energy Out (Exercise) 

Good daily amounts  Energy Balance ~ 45 KCal/Kg/FFM*  Resting Metabolism ~ 30 Kcal/Kg/FFM* *Loucks AB “Low energy availability in the Marathon and other Endurance Sports” Sports Med 2007; 37(4-5):348-352

Calculating Energy Availability (EA)  EA = (Energy IN – Energy OUT)

Fat Free Mass  Energy Cost of running = 0.86KCal/Kg/Mile  Consider our athlete: Weight 48Kg Body fat 6.5% FFM 44.88Kg

Daily Calories 1,200KCal, 10 Miles day-1  EA = (1200 – 0.86x48x10) / 44.88 =

17.6KCal/KgFFM

Estimating Calorie requirements  45 = (X – 0.86x48x10) / 44.88

 Desirable 45KCal/KgFFM

X = (45 x 44.88) + 412.8 = 2,432Kcal Deficiency of (2432-1200) (2432-1759) = 1,232KCal per day (= 673) 1) Energy cost of running in similarly trained men and women. Eur J App Physiol & Occ Physiol 59(3):178-183, Oct 1989

Mechanism  Low energy availability leads to

physiological rationing  Not due to „overtraining‟

Bone Mineralisation

Starvation/Famine  In times of famine, energy conservation

is critical  Internal homeostasis must be maintained despite limited resources (energy)  Non-essential physiological processes are curtailed to maintain the essential (rationing)

Hypothalamic Control  Hypothalamic

„energy‟ sensor receives input via Glucose, Leptin, mTOR, C75, AMPK  Energy deficiency leads to downregulation of Hypothalamic/ Pituitary hormones

Hypothalamic-Pituitary Axis Cortisol, Glucose Insulin, IGF-1

Hypothalamus GnRH

GHRH

T3 & T4, Leptin AMPK, C75, mTOR

LH/FSH

GH

IGF-1 Low energy availability

Oestradiol Progesterone

Energy in v Energy Out

Bone Mineralisation Menstrual Cycle

Functional Hypothalamic Amenorrhoea (FHA) Absence of „LH Surge‟ & Sex hormone Deficiency leads to Anovulation, failure of basal temp rise and luteal phase Deficiency (Ix – day 21 progesterone, USS Endometrial Biopsy, daily temp)

Eating Disorders versus Disordered Eating  Dietary restriction, compulsive exercisers, binge

eating and induced vomiting all occur  Thin because of Sport or Sport to hide thinness  Erroneous beliefs about weight & performance BUT  Exercise does not stimulate increased appetite1  Inadvertent inadequate calorie intake can occur in Athletes  High carbohydrate diets more prone to low calories

Hubert P et al „Uncoupling the effects of energy expenditure and energy intake:appetite response to short-term energy deficit Induced by meal omission and physical activity.‟ Appetite 1998;31:9-19

Bone Mineral Density  Bone mineralisation an energy-

dependent process (Osteoblasts – Formation v Osteoclasts – Resorption)  Hypo-oestrogenism  Oestrogen inhibits bone resorption by inhibiting production of cytokines IL1, IL-6, TNF-α

Clinical

Gold medals can be denied to even the best athletes if nutrition and Bone Health are not optimal.

Epidemiology  L.E.A. 36% in

female athletes in one study  Eating Disorders up to 31%  Amenorrhoea up to 65%  Osteopaenia 2250%

Identification and Screening  A „silent‟ condition  Ask about diet / training / menses /

stress fractures/soft-tissue in at risk individuals  If Ovulatory cycle is outside of normal range (21-28-35 days)  Tell athletes that „missing periods‟ is a sign that something is not right

Investigation – Diet & Eating Habits  Food Diary  Eating Disorder questionnaire1  Training load (mileage/intensity)  Leptin ↓ Urinary Ketones ↑

Hypometabolic endocrine profile: ↑TSH, ↓T3 ↓T4 ↓Insulin: ↑Cortisol ↓IGF-1/GH 1) Eating Disorder Inventory (EDI) Garner et al 1983

Investigation – Menstrual Function  ↓Oestrogen & Progesterone (Day 21)  ↓or absent LH Surge  Failure of basal temperature to rise in luteal

phase  Thickness of Endometrium in Luteal Phase – biopsy or USS  Ix 2ndary Amenorrhoea – Prolactin/LH/FSH/Testosterone)  USS – Polycystic or microcystic* *Denotes pre-menarchal ovaries/low sex hormone levels

Investigation – Menstrual Function

Investigation – Bone Health  DEXA Scan (in young women use Z-

Score, repeat 18months)  

Z = -1 to -2 ‘low BMD for age’1 Z = < -2 ‘Osteoporosis’2

 Vitamin D & Calcium & PO4

 Osteocalcin / P1NP – bone formation  Serum / Urinary NTX – bone resorption 1) International Society for Clinical Densitometry (ICSD), 2) ACSM

Vitamin D  Limited evidence that Vitamin D has a

role in strength/power and athletic performance  Aim to keep levels at higher end of normal – 150nmol/L

Management  Psychology/Ψ if Eating Disorder present  Explain importance of energy in adaptation & recovery  Dietician – increase total calorie intake (Fat, CHO &   

 

Protein) BMI > 19, Body Fat – 20%, 45KCal/KgFFM/day Contract to gain Weight up to BMI 19 and improve diet before being allowed to train fully - Coach Calcium 1200mg and Vitamin D 1000iu  1,25-(OH)2D3 better than D2 (absorption, potency, halflife)  Tuna, Eggs, Milk Reduce training ~10% – Coach Oestrogen? – contentious – masking symptoms

Stress Fractures  Relative Rest followed by progressive

loading  Maintain other components of fitness by non-impact cross-training (HR/VO2 > 90%)  NWB → TWB/PWB → FWB  Aircast Boot  Bisphosphonates / Teriparatide (PTH)

Prevention  ASK – Do you have regular periods?  Weight loss?  BMI/Weight  Education  Dietary History

What about men?

Toughest part of your sporting life: “A stress fracture of the pelvis, which was awful...” Mo Farah - Telegraph

Fatigue/Underperformance  Low Energy Availability can present

(particularly in men) with Fatigue and underperformance, delayed recovery from training etc.

Overview

Information  www.acsm.org  www.olympic.org  www.femaleathletetriad.org

Thank You