Does estrogen affect muscle damage and repair? How does hormone replacement impact performance? Is weight gain during menopause inevitable? Learn the answers to these and other questions related to women, hormones and exercise.
1. What hormonal changes are observed in boys and girls at puberty?
At puberty, girls develop more adipose tissue, owing to their estrogen levels, and boys develop more muscle mass, owing to their testosterone levels (Isacco, Duché & Boisseau 2012).
2. What is the female athlete triad?
The three components of the female athlete triad are lack of a menstrual cycle, low bone mineral density and eating disorders. The triad occurs in females whose training levels exceed energy availability. Health consequences include cardiovascular, endocrine, reproductive, skeletal, gastrointestinal, renal and central nervous system complications. Psychological problems include low self-esteem, depression and anxiety disorders.
The first goal of treatment for someone suffering from the female athlete triad is boosting energy availability by increasing intake of foodstuffs and/or reducing energy expenditure. Females with eating disorders or disordered-eating patterns should be referred for nutritional counseling (Nattiv et al. 2007).
3. What is menopause?
Menopause is the profound transition in a woman’s body when menstruation ceases. A fundamental etiology associated with menopause is the intricate link between estrogen metabolism and the autonomic nervous system. Irregular menstrual cycle changes are usually the first symptom.
Lower fertility during the perimenopausal stage (transition into menopause that begins 8–10 years before menopause) of a woman’s life results in significant drops in estrogen levels. The term vaginal atrophy refers to an inflammation of the vagina as a result of the thinning and shrinking of the tissues, as well as decreased lubrication caused by lack of estrogen.
Hot flashes—sudden feelings of heat in the upper body—may start in the face, neck or chest and then spread upward or downward (depending on where they started). Skin on the face, neck or chest may redden, and a woman usually starts to sweat. Heart rate may suddenly increase and may become irregular or stronger than usual. Hot flashes generally occur during the first year after a woman's final period. Disturbed sleep problems are typically caused by night sweats, insomnia or anxiety.
Difficulties falling asleep and staying asleep increase as women go through menopause. Urinary problems tend to be more likely during this period. Moodiness often goes hand in hand with sleep disturbance. There may also be some hair loss or thinning during menopause (Nordqvist 2009).
4. Are women at increased risk for cardiovascular disease after menopause?
Yes. Women who are peri- and post-menopausal are at an increased risk, due to a decrease in the female sex hormones.
5. Is walking as effective as vigorous exercise for the prevention of cardiovascular events in women?
Manson et al. (2002) compared walking and vigorous exercise, along with hours spent sitting, as predictors of the incidence of coronary events and total cardiovascular events among 73,743 postmenopausal women aged 50–79 who were part of the Women’s Health Initiative Observational Study. Results indicated that walking and vigorous exercise were associated with substantially fewer cardiovascular events among postmenopausal women, irrespective of race or ethnic group, age and body mass index. Prolonged sitting predicts increased cardiovascular risk.
6. Does estrogen affect skeletal muscle damage, inflammation and repair?
Yes, estrogen may positively lessen skeletal muscle damage and inflammation from exercise. Theoretical evidence suggests estrogen may encourage recovery and repair of muscle as well. This finding is preliminary, and more research is needed to explore mechanisms and further applications (Tiidus 2003).
7. Does hormone replacement affect exercise performance?
Green et al. (2002) found an effect only during high-intensity aerobic exercise. Systolic blood pressure at peak exercise in women taking hormones was lower than in women not taking hormones at almost identical levels of oxygen consumption and cardiac output. Further research is needed in this area.
8. Is weight gain during menopause inevitable or preventable?
The years during menopause are associated with weight gain and increased central adiposity. Body fat distribution and body composition changes may be due to the hormonal changes and loss of muscle mass occurring during the menopausal transition. The one factor most consistently related to weight gain during menopause, however, is physical inactivity. To avoid weight gain, women should make regular physical activity a priority (Simkin-Silverman et al. 2003).
For an in-depth look at how female physiology, metabolism and energy expenditure connect, plus a full reference list, please see “Women, Hormones, Metabolism and Energy Expenditure” in the online IDEA Library or in the July–August 2013 issue of IDEA Fitness Journal.