“The menstrual cycle has long been viewed as a barrier to training and performance” says Dr Richard Burden, physiology technical lead at the English Institute of Sport (EIS). Nowadays, professional sportswomen are beginning to talk more openly about their menstrual cycles and its impact on performance. It is a crucial moment for female athletes to open the conversation and allow training prescriptions to be more tailored to female physiology. As it turns out, having a period is a natural ergogenic aid that can be used for maximising training gains in the weights room or any chosen sport.
The Cambridge University Boat Club (CUBC) women did exceptionally well this year, winning both their Boat Race and their reserves race. Their success was, in part attributed to strength training according to menstrual cycle, tracking menstruation, screening for low energy availability (LEA) and relative energy deficiency in sport (RED-S). All of which has never been done before on this scale or within the rowing community, as per the author’s knowledge. However, in order to understand training periodisation according to menstrual cycle one needs to appreciate the physiology and strength training prescription behind it.
Understanding and unriddling menstrual cycle.
Whilst the average cycle is 28 days long, very rarely will individual athletes actually have a 28 days long menstrual cycle. It will more likely range between 21 to 40 days. It is crucial that sportswomen track their cycle (via app or pen and paper), in order to better understand and predict recovery, appetite swings and general aches. Day 1 (first day of bleeding) through day 14 are called a follicular phase, days 15 through 28 (last day before period) are referred to as a luteal phase. Ovulation happens right in the middle of a cycle.
For performance, it means the most preferable time for intense training and increased volume is during menstruation, as the hormones are most favourable. Naturally, female competitors worry about having their period during a big event, yet physiologically it is the most optimal time for physical activity. Indeed, the best remedy to navigate cramping as well as aches and pains is movement.
Once the body knows pregnancy is not an option, it can naturally relax and re-focus energy systems on locomotion and exertion. Similarly, the homeostasis continues through the follicular phase right until ovulation, just before luteal phase kicks in. In terms of strength training, researchers found that women could make greater strength gains and exert higher rate of force development when strength training in follicular phase versus luteal phase. Additionally, in the first part of menstrual cycle neuromuscular adaptation, recovery, pain perception and thermoregulation are the most optimal.
The event calendar cannot be moved around to suit physiology. So what happens when athletes must race during their high hormone phase? It has been reported that VO2max and lactate threshold remain relatively constant throughout the cycle. This indicates that endurance athletes are able to score a personal best even during premenstrual syndrome (PMS). Per contra, athletes in team sports or stick-and-ball sports, may notice a drop in performance when in high hormone phase. Luckily, there are nutritional interventions that can be implemented for athletes having to compete with PMS. The main intervention would be to bring the systemic inflammation down via specific foods, supplements and most of all an increased protein and complex carbohydrates intake.
When athletes are on hormonal contraception, then everything discussed above does not apply. Hormonal contraception supresses ovulation.
Some female athletes do not have a menstrual cycle (amenorrhea): they will need a specific intervention which mainly consists of a nutritional strategy and a hypertrophy-specific training program.
Women in general have a long history of being shamed into not talking about menstruation. Most of the time female athletes deal with the menstrual cycle in silence or amongst each other. Although this can still be a significant hurdle to overcome, a multidisciplinary team of coaches could make the process easier for everyone. The best approach would be to appoint one senior member of staff for example a sport psychologist, nutritionist or a strength and conditioning coach, preferably female. A designated member of coaching team could then become a contact point, for athletes to discuss any issues related to periods. The worst thing coaches could do is to randomly ask their athletes about menstruation during a training session.
At Cambridge University Boat Club (CUBC women’s programme) the lead strength and conditioning coach was a designated person. Prior to introducing training periodisation according to menstrual cycle, athletes were asked to track their cycle and fill out a health questionnaire. Since this is sensitive data a consent form was obtained from each athlete. The questionnaire included several questions including LEA and RED-S. To elaborate, LEA occurs when athletes don’t eat enough food to support the physical demands of training, in other words, energy expenditure is higher than energy intake. Once in this state, a cascade of hormonal disruption is triggered which may impair health and performance. In response to a prolonged energy deficit, female body stops processes associated with growth & reproduction to re-focus on thermoregulation, cellular maintenance and locomotion. If not addressed appropriately at this stage athletes would be at risk of developing RED-S, previously known as female triad (lack of period-amenorrhea, osteoporosis, eating disorders).
In 2014 The International Olympic Committee (IOC) issued a statement that the female triad is a syndrome which is the result of “relative energy deficiency that affects many aspects of physiological function including metabolic rate, menstrual function, bone health, immunity protein synthesis cardiovascular and psychological health”. By using a questionnaire designed to monitor athletes who might be at risk of developing both LEA and RED-S, coaches got an insight into athletes who could potentially lose their period.
Amenorrhea is not only specific to lightweight rowers it also occurs in open weight rowers and is a major health welfare issue. The longer the amenorrhea lasts the higher the risk of developing osteoporosis, eating disorders and thyroid problems. It would be advisable to refer these athletes to see a GP.
There are three different groups of athletes according to the exposure to different levels of hormones which dictates the training load. 1. Normal menstrual cycle (divided into low & high hormone phase). 2. Athletes on hormonal contraception 3. Hypertrophy group (LEA or amenorrhea). Athletes are responsible for tracking their cycles, however there are applications that could be used in order to collect larger data and correlate it with technical training.
Rather than working with traditional 6-8 weeks linear mesocycles, for female athletes a mesocycle would be closer to 6 weeks (including low and high hormone phase). A lot will be trial and error, but at the same time athletes become more efficient at recognising when they are at the peak of their capabilities. A periodised training program correlating with female physiology allows coaches to avoid chronic fatigue, hit training parameters and most of all improve performance.
In conclusion, coaches should screen at the beginning of the season for LEA and RED-S as well as encourage their athletes to track their menstrual cycle. A senior member of the coaching staff should be a designated person who is responsible for talking to athletes about their menstruation. Traditional training periodisation has been designed based on male data, therefore it’s not applicable for female athletic population. Women will benefit greatly from a periodised training programme according to menstrual cycle. Initially, it might look like a logistical nightmare with all the different programs, yet the training parameters will improve with time. Athletes with amenorrhea – after seeing a GP – should work closely with a nutritionist and have a separate training program focusing on hypertrophy.
“It’s a nice notion that we can do the same training program as men and adapt in the same manner, we have a totally different physiological environment.” Says Dr Hagstrom