Gender Differences & Training Implications

Training Considerations for the Female Athlete

“Decreasing Potential for Injury and Increasing Functional Carryover”

Trent Nessler, DPT, MPT

Statistics Related to Female Athletes

• Until the late 60s/early 70s few women participated in athletic activities

• In 1997: 1 in 3 girls now participate in sports compared to 1 in 27 in 1971

• 42% of Olympians in 2000 were women compared to less than 1% in 1904

• In 2000 52% of high school girls do not take PE classes

• Teens (men and women) who participate in regular physical activity have increased peak hip bone density – why is this important?

Statistics Related to Female Athletes

• NCAA Injury Surveillance System (ISS) support the notion that there are generally slightly higher injury rates in women’s sports than in men’s with comparable rules

• Frequently, men’s and women’s sports can not be compared because of differences in rules

• Increasing evidence of higher rates of severe knee injuries, specifically ACL injuries associated with soccer and basketball

• So what are some of the physiological differences between men and women?

Outline

• Physiological differences and what training considerations need to be made

• Variations in – Body size– Body composition– Muscle Tissue– Energy Metabolism– Circulation– Cardiorespiratory

Outline

• Increased injury rates for women and some of the hypothesis

• Some of the common orthopedic injuries

• Other factors affecting the female athlete

• Training Considerations

Body Size Differences

• Height and weight– Peak height for girls reached between 10.5 to 13 years

compared to 12.5 to 15 years for boys (growth rate)– Menarche (menstruation) occurs ~1 year after the peak height

velocity is achieved• Current research shows average now 10.9 years of age• Due to the higher concentration of hormones in meats children are

eating

– Speculate that women menopause will lower from 45-50 years of age secondary to earlier menstruation and ovary burn out (What is that?)

– Adult stature is reached by 17 to 19 for girls and early 20s for boys

Body Size Differences

• Skeleton– Women have a wider, shallower

pelvis than men – adds to increased Q angle at the knee in women, speculated for increase potential for knee injuries in women

– Women are 4xs more likely to develop osteoporosis than men due to estrogen withdrawal

– Peak bone mass achieved around age 30

• May be changing secondary to earlier onset of menarche

– Rate of bone loss accelerates with estrogen withdrawal but can be attenuated with exercise

Training Considerations

• Women may benefit from earlier training protocols including resistance training which may– Decreases potential for osteoporosis later in life by

increasing peak bone mass– Decreased potential for knee injuries

• WB resistance exercise may help coordination since peak growth rate higher than that of boys, therefore can add to decreased balance– Why?

Body Size Differences

• Body composition– Adult women have 8-10% more body fat than

men• Sedentary college age women average 23-27% body

fat

– Active women have lower body fat than sedentary college aged men (15-18% for women)

– The ratio of lean body mass to fat ratio changes from 5:1 to 3:1 between the beginning of puberty and the beginning of menstruation (% body fat increases with menstruation)

Training Considerations

• Should educate females on differences in body composition

• Educate on healthy proper diet modification and importance for improving– Athletic performance – 1% dehydration adds to 10%

decrease in performance.– Recovery from injury – without proper hydration and

protein intake, you can slow the healing process by 3-4 weeks

– Should include education on water, what is the recommended amount?

• .5 to 1.0 oz per lb body weight –varies on activity level

Training Considerations

• Journal of Epidemiology (June 2002)– Women who drink 5 glasses of water a day reduce

potential for heart disease by 41%– Men who drink 5 glasses of water a day reduce the

potential for heart disease by 56%– Nearly 50% of the American population is considered

clinically dehydrated• Educate on Caffeine, diuretic and postulated to

increase bone loss– Recommended daily dose 420 mg/day, average over

800-1600 mg/day– For every 10 mg over, add 1 oz of H2O

• Educate on what realistic fitness goals are!

Body Size Differences

• Muscle tissue– Muscle fiber and total muscle

cross sectional area of women average 60-85% of these areas in men

– Portion of fast and slow twitch fibers is equal in men and women

– The differences in absolute strength between sexes virtually can be eliminated when the strength is expressed relative to fat free weight

– The difference in muscle strength between trained women and men appears to be explained by muscle mass size

Training Considerations

• Women can participate in sports that require fast and slow twitch fibers

• When assessing absolute strength, should figure relative to lean body mass

• Women can make similar strength gains as men

Energy Metabolism

• Resting metabolic rate in women is 5-10% lower than in men

• Training considerations– Women will burn less calories per hour– Educate on and correlation to percentage body

fat differences in men and women

Circulatory Differences

• Hemopoietic system – Adult men have 6% more RBCs than women– Adult men have 10 to 15% higher hemoglobin

concentration and hematocrit compared to women

• Anemia– Women are at a greater risk for iron deficiency anemia

than men because of a lower dietary intake coupled with greater iron loss

– Sports Anemia an athlete may have normal red blood cells numbers but an expanded plasma volume which results in hemodilution

Training Considerations

Women transport less oxygen than men secondary to less hemoglobin and RBCs

Could add to quicker fatigue in women Should be educated on diet and iron

supplementation, especially when participating in exercise

Cardiorespiratory Capacity

Lung volumes Women have smaller thoracic cage, results in lower lung

volumes Total lung capacity W=4200 ml, M=6000 ml Vital capacity W=3200 ml, M=4800 ml Residual volume W=1200 ml, M=1000 ml

Heart size and stroke volume Women have smaller heart volume, resulting in lower

stroke volume and therefore lower maximal cardiac output

At the same VO2max, women have a higher heart rate than men

Cardiorespiratory Capacity

Blood pressure Girls reach a plateau between 15-17 years of

age and men continue to increase until about the age of 20

Aerobic power (VO2max) Peak VO2max is achieved for both sexes

between the ages of 16 to 20 years

Cardiorespiratory Capacity

Aerobic power Differences in body composition and the oxygen

transport system account for much of the sex differences in VO2max

52% greater in men 30% greater in men when expressed relative to body

weight 15% greater when calculated relative to fat free weight Takes the heart 3 minutes to respond to a change in

intensity of exercise. If measuring HR, give 3 min after change in intensity before you

measure.

Training Considerations

• Less cardiorespiratory capacity in women adds to decreases endurance when compared to men secondary to decreased cardiac output and decreased VO2max

• Should be addressed with a well rounded fitness program

• Should Use karvonen formula:Target HR/6 = [(HRmax – HRrest) *.6-.8] + HRrest

HRmax = 220-ageHRrest = HR for 1 min @ rest

• Get your target HR and devide by 6. Will give you HR for a 10 sec count.

Higher ACL Injury Rates in Female Athletes

• Hypothesis– Ligament size smaller– Inherent ligament laxity – due to progesterone released

during menstruation– Smaller notch dimensions in the pelvis– Decreased muscle strength– Decreased coordination– Different limb alignment– Decreased level of skill

• Level of skill– all related to women get involved in sports later in life than males

Higher ACL Injury Rates in Female Athletes

• Kinematic Differences between Men and Women– Indicating weaknesses in the G. med and hip ER and/or decreased

proprioception.– Adding to increased Valgus and IR Stresses at the knee with

squatting.– Gives indication of how forces may be attenuated at the knee with

walking, running, athletic activities.

Zeller ect al. “Differences In Kinematics and Electromyographic Activity Between Men and Women during the Single Legged Squat”. American Journal of Sports Medicine. May/June 03. 449-56.

Training Considerations

• Exercise may not be able to effect all of these factors however can improve– Strength– Coordination– Level of skill– Overall muscle and cardiopulomonary

function/endurance

Common Orthopedic Injuries in the Female Athlete

• Patellofemoral joint syndrome

• Shoulder impingement syndrome– Especially in racket sports,

swimming, and throwing sports– Female swimmers with shorter

arm length and shorter bodies must take more strokes and hence increased number of repeated shoulder insults to cover the same distance

– Generalized increase in joint laxity increases joint subluxation as well as increased risk for impingement syndrome

Common Orthopedic Injuries in the Female Athlete

• Over pronation leads to a variety of foot, knee and LE over use/stress syndromes including plantar fasciitis, and post tib tendonitis– Bunions– Inflammation of the bursa overlying the medial

prominence of the first metatarsal• Result from varus deformity of the first metatarsal

Common Orthopedic Injuries in the Female Athlete

• Increased foot pronation can cause increased stress on the first phalanx, hence aggravating a hallux varus deformity and irritating existing bunions– May result from shoe wear designed for the male foot

• Idiopathic scoliosis– 85% of adolescent idiopathic scoliosis occurs in girls– Right thoracic curve is the most common

Stress Fractures Quote

“The positive influence of exercise on bone can be attenuated by environmental

conditions, such as hormone status and nutritional status, and may not make up for the influence of the hormonal changes in an

individual”

Dalsky, 1987

Other Factors Affecting Stress Fractures in Women

• Diet

• Decreased lower extremity strength in women

• Training errors

• Biomechanical alignment

Urinary Incontinence in the Female Athlete

• Exercise induced urinary stress incontinence– Many women experience urine leakage during

exercise– Hypothesis – associated with val salva with

exercise and lifting and due to weak pelvic floor musculature

Training Considerations

• Training protocols and education should not only be created to increase performance in the sport but also address and attempt to reduce some of the most common orthopedic problems in women

Program Development For Female Athlete

• Should come after a through assessment of the athlete, determining their– Orthopedic Hx– Previous medical Hx

• Assessment of the five component of fitness– Cardiovascular endurance

• Three minute step test

– Muscular strength and endurance• MMT

– Flexibility• Gonimetric measurements and sit and reach

Program Development For Female Athlete

• Body composition– Caliper

• Consideration of orthopedic injuries women susceptible to with participation in the given sport

• Development and implementation of exercise program that will ensure maximal carry over to sport

Summary

• Physiological differences and what training considerations need to be made

• Variations in – Body size– Body composition– Muscle Tissue– Energy Metabolism– Circulation– Cardiorespiratory

Summary

• Increased injury rates for women and some of the hypothesis

• Some of the common orthopedic injuries

• Other factors affecting the female athlete

• Training Considerations

Contact

Trent Nessler, PT, DPT, MPT

(e) [email protected]