The Effects Of The Menstrual Cycle On Training
Despite being female. Despite having an A level in biology, this blog post has taken a while to write, due to the amount of research I have had to do. Whilst the topic is more beneficial for females, PTs/coaches who are male may also find it useful to read to understand how their clients menstrual cycle may affect their clients training.
Therefore, the purpose of this blog post is to highlight some research surrounding the menstrual cycle and the effects of this on training.
Stages of menstrual cycle
Let’s begin by discussing the different stages of the menstrual cycle. If you’re already a guru at this (I personally knew nothing lol), then skip to the section ‘So how does all of the above impact my training?
’Menstruation: The period. Elimination of the thickened lining of the uterus (endometrium) from the body through the vagina. Menstrual fluid contains blood, cells from the lining of the uterus (endometrial cells) and mucus. The average length of a period is between three days and one week.
Follicular phase: starts on the first day of menstruation and ends with ovulation. Effect on hormones= oestrogen rise in preparation for an egg to be released.
Ovulation: release of a mature egg from the surface of the ovary. Oestrogen peaks beforehand and then drops shortly afterwards.
Luteal phase: egg bursts from its follicle, but the ruptured follicle stays on the surface of the ovary. For the next two weeks or so, the follicle transforms into a structure known as the corpus luteum. If pregnancy does not occur, the corpus luteum withers and dies, usually around day 22 in a 28-day cycle. The drop in progesterone levels causes the lining of the uterus to fall away. This is known as menstruation. The cycle then repeats.
So how does all of the above impact my training?
The feature image of the blog post shows numerous studies and their effects on strength. Green highlight stands for increased strength, whilst red found a reduction in strength. Grey found no difference. As you can see, increased strength was found during the late follicular and ovulation stages.
Women tend to be stronger during the follicular phase when the estradiol to progesterone ratio is high. After ovulation, right about when the ratio reverses, strength levels decrease until the ratio becomes positive again. Moreover, in a study focussing on leg strength, the legs with more workouts in the follicular phase gained 42% more strength (maximum isometric force) and 46% more muscle (sum of 3 diameters) than the legs trained mostly in the luteal phase. [Sung et al 2014].In another study, it was concluded that…. “Our results indicate that, high frequency periodized leg resistance training during the first 2 weeks of the menstrual cycle is more beneficial to gain power, strength and to increase lean body mass, than the last 2 weeks [Frisen et al 2017]. Whilst the remit of this blog post is more related to strength based training, it is important to also note the impact of the menstrual cycle and cardiovascular training. Whilst strength training research tends to lean towards the luteal phase not being beneficial to training, the study below showed an improvement in cardio training during the luteal phase.
Oestrogen impact:
One of the most important actions of oestrogen during the luteal phase is its effect on the cardiovascular system. This may benefit submaximal exercise of long duration by increasing intramuscular and hepatic glycogen storage and lipid synthesis (Reilly, 2000). Glycogen sparing effects due to enhanced lipolysis in muscle and greater use of free fatty acids has been seen at rest and during exercise at this phase (Frankovich & Lebrun, 2000).
Conclusion
A magnitutude of research shows increased strength was found during the late follicular and ovulation stages. Whilst, improvements in cardio performance has been found during the luteal phase. It is important to note that the purpose of this blog post isn’t to say that during the luteal phase, you are going to see massive depletions in strength or that you’re going to be Paula Radcliffeesque in your cardio ability. It is more to encourage you to think about the effects of your menstrual cycle on your hormones and training.
Moreover, as you can see in the graph, many studies showed no effects on training and it is important to consider that too. The best way to find out how your strength differs during your menstrual cycle is to track it. It is also important to consider other variables. Could it be that the phases during the start of the cycle lead to larger strength gains due to the impact on hunger and satiety during menstruation? Is it that during menstruation, you are eating more and eating more calories is fuelling this strength gain as opposed to the hormonal changes themselves?
Either way, I urge you to be more mindful of your menstrual cycle and training and think about how it affects you and your own training.The research listed is all well and good, but we are all unique and the only way to find out if there is a link with your training and menstrual cycle is to BE YOUR OWN EXPERIMENT. Start to track how your training feels vs what point in your cycle you are at. This is the best way to find out. Period.
ReferencesFrankovich, R. J., & Lebrun, C. M. (2000). Menstrual cycle, contraception, and performance. Clinics in sports medicine, 19, 251–271.Frisen et al 2017. Effects on power, strength and lean body mass of menstrual/oral contraceptive cycle based resistance training. 2017 Jan-Feb;57(1-2):43-52. Doi: 10.23736/S0022-4707.16.05848-5. Epub 2015 Nov 11.Reilly, T. (2000). The Menstrual Cycle and Human Performance: An Overview. Biological Rhythm Research, 31, 29–40.Sung E, Han A, Hinrichs T, Vorgerd M, Manchado C, Platen P. Effects of follicular versus luteal phase-based strength training in young women. Springerplus. 2014;3:668. Published 2014 Nov 11. doi:10.1186/2193-1801-3-668https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/menstrual-cycle#lp-h-1