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 menstrual cycle, and what are its distinct phases?
The human menstrual cycle, designed to prepare a woman’s body for pregnancy, takes an average of 28 days. Usually, once a month the uterus grows a new, thickened lining (endometrium) that can hold a fertilized egg. If there is no fertilized egg to start a pregnancy, the uterus then sheds its lining.
The menstrual cycle has three distinct phases: the follicular phase (FP), ovulation and the luteal phase (LP). The FP begins on day one of menstruation and lasts about 10–14 days, until ovulation (the monthly release of a mature egg from an ovary). The LP, or secretory, phase is the second half of the menstrual cycle, after ovulation. Estrogen and progesterone concentrations vary between the phases.
3. Does lactate accumulation during exercise inhibit fat breakdown?
No, lactate accumulation from higher-intensity exercise does not inhibit lipolysis (Jeukendrup 2002).
4. 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).
5. 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 inflammation, thinning and shrinking of the vaginal 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.
Difficulty 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).
6. 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.
7. Are women at increased risk for cardiovascular disease after menopause?
Yes. Women who are peri- and post-menopausal are at an increased risk, owing to a decrease in the female sex hormones.
8. 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).
9. 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.
10. 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).
Considerations For Active Women
- Physical activity should be a priority at all ages, particularly after menopause.
- Women use less fat and more carbohydrate to fuel exercise at submaximal levels.
- Endurance performance may rise during specific phases in the menstrual cycle.
- Resistance training can boost the hormones affecting bone formation, especially for women of reproductive age.
- Trainers should be on guard for the female athlete triad.
To read the full article that ran in the 2013 July-August issue of the IDEA Fitness Journal click here.