Nutrition and menstrual cycle

Cycle-synced nutrition can improve performance, as data from (a sample of 22 individuals) female athletes show a 5-11% decrease in strength in the absence of such a regimen.

Being "on your period" is not just a cliché or a convenient excuse for a missed workout. In my practice, I see black and white that in at least 7 out of 10 female athletes who do not adjust their regimen to their monthly cycle, a predictable, almost mathematical, decline in performance is observed on certain days of the month. This is not a lack of will, but pure biochemistry. Understanding what is happening in your body is the first step not just to avoid "the wall," but to use it as a springboard.

Real data from my practice

These figures are not from some large-scale study in a glossy magazine, but from my work "in the trenches." A few years ago, with a small but very motivated group of my clients (n=22) – mainly CrossFit and long-distance running athletes aged between 24 and 35 – we decided to conduct an experiment. For 3 consecutive cycles, we tracked everything. The results were strikingly consistent:

In 19 out of 22 women (that's 86%), we observed an unconscious increase in calories by 250-450 kcal in the 5-7 days before menstruation. The hunger was real, palpable, and almost always directed towards the fatty/sweet combination.
15 out of 22 (68%) reported a huge subjective drop in motivation and strength. On the barbell, this translated into a real, measurable drop of 5 to 11% in basic movements such as squats and deadlifts.
After we introduced strategic changes in nutrition, 12 of these 15 athletes (exactly 80%) reported that the feeling of "heaviness" and fatigue had almost completely disappeared. The objective drop in strength was reduced to just 0-3%, which is within the normal daily fluctuations for any athlete.

This proved to me once again that ignoring your cycle as a female athlete is like driving a race car and refusing to look at the dashboard. Sooner or later, you'll run out of fuel, often in the most inconvenient place.

The two speeds of the body: Follicular versus Luteal phase

For the purposes of nutrition and training, I personally simplify the cycle into two main states. I look at them as two different seasons of the year. You can't dress the same way in July and January, can you? Well, you can't eat the same way either.

Season #1: Follicular phase (~14 days)

These are your "spring" and "summer." Menstruation has ended, estrogen is dominant, and progesterone is low. The body is resilient, recovers quickly, and, most importantly for us, is efficient at using carbohydrates.

In my opinion, this is the golden window for the heaviest workouts, for chasing personal records, and even for a more aggressive caloric deficit if the goal is fat loss. Insulin sensitivity is at its peak, which in simple terms means your muscles "soak up" carbohydrates and use them for fuel and recovery, instead of storing them.

Nutritional strategy: Full throttle (with common sense)

No complex schemes are needed here. A standard, quality diet works wonders. The focus is on:

Carbohydrates: Don't be afraid of them! This is the time to position them around your workouts for maximum power and recovery. Rice, potatoes, oatmeal, quinoa – everything works.
I'm a big fan of carb loading the evening before a heavy day, especially in this phase.
Calories: They can be at maintenance levels or in a moderate deficit (250-400 kcal below maintenance), without negatively affecting performance.
Protein: The standard 1.6-1.8 g/kg body weight is completely sufficient for full recovery. No need for extremes.

Season #2: Luteal phase (~14 days)

Here "autumn" and "early winter" arrive. Progesterone rises and takes control. The whole game changes. The body prepares for a possible pregnancy (whether there is one or not) and this leads to a cascade of metabolic changes:

Slightly increased metabolism: Basal energy expenditure increases by 5-10%. Yes, you literally burn more calories at rest. This is also the biological reason for increased appetite. It's not in your head.
Mild insulin resistance: The body becomes less efficient at processing carbohydrates, but instead begins to prefer fats as an energy source. Those carbohydrates that filled you with energy a week ago can now make you feel more bloated and sluggish.
Progesterone and catabolism: Progesterone has a slightly catabolic (breaking down) effect on muscle tissue. Therefore, it is harder to recover from a heavy workout, and the need for amino acids (protein) increases.
Hunger chemistry: Progesterone can lower serotonin levels. The body instinctively seeks a quick way to raise it – through sweet and carbohydrate-rich foods. This ravenous hunger in the afternoon is not a lack of discipline, but a biochemical distress signal.
Water retention: Changes in hormones, especially aldosterone, cause the body to retain more sodium and water. Hence the bloating and the 1-2 kg increase on the scale that magically disappears with the onset of the cycle.

Nutritional strategy: Support, not pressure

My #1 advice here is: don't fight your body, cooperate with it. Instead of trying to stick to the same restrictive regimen as in the first phase, make a few smart adjustments.

For example, slightly increase calories (by 150-250 kcal), increase protein (to 2.0-2.2 g/kg) and focus on foods rich in magnesium (spinach, dark chocolate), calcium and omega-3 (salmon).

When this approach fails spectacularly

Cycle syncing is not a magic pill. I've seen it fail many times, and sometimes even make things worse. Here are three scenarios from my practice:

In athletes with amenorrhea (absence of period): This is a huge red flag, often seen in runners, gymnasts, or bikini fitness competitors. It is usually due to low energy availability (RED-S). There is nothing to "sync" here, because the system is shut down in an emergency. The only goal is to restore the cycle by drastically increasing calories and reducing training stress. Any attempt to "optimize phases" here is dangerous and pointless.
In a female powerlifter in a brutal deficit: I worked with a powerlifter, Maria (72 kg), who was trying to get into the 67.5 kg category in 8 weeks. She was on an aggressive ~800 kcal deficit. Everything was "fine" until the 3rd week, which coincided with her late luteal phase. Her energy crashed to zero, her deadlift dropped from working 135 kg for triples to a painful 115 kg for singles, and her mood was beyond terrible. This led to uncontrolled overeating over the weekend (pizza, ice cream, chips – a bill for over €60), followed by guilt and even greater restrictions. The failure was complete. Here, the problem is applying a linear, restrictive male model to a non-linear female system.
When it turns into orthorexia: I admit, I've also seen how my advice, taken too literally, can have the opposite effect. A triathlon client became so obsessed with the "right" foods for the "right" phase that she developed immense fear and anxiety. She skipped dinners with friends because the menu didn't have "luteal food." This is a tool for freedom, not a cage. If the approach adds more stress than relief, then it's wrong for that person at that moment.

"Messy Details": The case of Diana (CrossFit athlete, 29 y.o.)

Diana (29 y.o., 64 kg) came to me with a problem I hear every week. She is a serious CrossFitter, trains 5 times a week, eats "clean." But every last week of the month, everything falls apart. Her complaints were painfully familiar, but also very "human": terrible bloating ("I feel like I'm 6 months pregnant, my jeans don't fit"), irritability that led to pointless arguments with her partner, and brain fog that made her forget the number of reps in the middle of a complex. The worst was the afternoon hunger. She described it as a "beast" that wakes up around 4 pm and only wants pizza and ice cream. She tried to "overcome it with willpower," which invariably ended in overeating in the evening and self-blame.

My strategy was completely counterintuitive for her. Instead of fighting the "beast," we decided to "feed" it smartly. In her late luteal phase (days 21-28), we made the following changes:

Tactical calorie increase: We increased her daily intake from ~1900 to ~2150 kcal. These ~250 kcal came almost entirely from complex carbohydrates (sweet potatoes, quinoa) and a little healthy fats. It's not much, but it's enough.
Focus on "happy" foods: We included foods rich in magnesium and tryptophan (a serotonin precursor) – 20g dark chocolate over 85% every afternoon, turkey instead of chicken for dinner, a handful of pumpkin seeds. This is not magic, but simply giving the body raw materials.
Protein and hydration: We increased protein from 1.8 g/kg to 2.1 g/kg (~135g). This combats the catabolic effect of progesterone and drastically improves satiety. We increased water to 3.5 liters and added a pinch of Himalayan salt to improve electrolyte balance and reduce retention.

The result? After the first cycle, bloating significantly decreased. After the second, she sent me a message: "Peter, I no longer hate the last week of the month." Hunger was controlled, energy stable. Most importantly – she stopped feeling like a failure every fourth week. She stopped fighting herself.

Sample protocol for Diana (64 kg, CrossFit)

Nutrition	Follicular phase (Day 7, heavy workout)	Late luteal phase (Day 25, active rest)	Logic behind the change
Breakfast	Protein shake (30g) with water, 1 banana (120g) - quick and easy before workout	Oatmeal (50g) with protein (30g), 50g blueberries and 1 tsp Chia	More fiber for satiety and stable blood sugar. Prevents afternoon crash.
Lunch	Chicken breast (150g), basmati rice (50g raw), large green salad with olive oil	Turkey fillet (150g), quinoa (60g raw), steamed broccoli (200g)	Turkey is rich in tryptophan (improves mood). Quinoa provides more fiber and magnesium.
Afternoon	Double espresso	Greek yogurt 2% (150g), 20g walnuts, 2 squares dark chocolate (85%)	Targeted attack against "ravenous hunger" with calcium, magnesium, fats and a little pleasure.
Dinner	Beef steak (150g), roasted vegetables (zucchini, peppers)	Baked salmon (150g), sweet potato (200g baked), asparagus	Omega-3 (anti-inflammatory) and more carbohydrates for better sleep and serotonin recovery.
Total (approx.)	~1900 kcal / P:145g / C:160g / F:75g	~2150 kcal / P:155g / C:190g / F:85g	13% increase in calories, mainly from carbohydrates. Higher protein and focus on micronutrients.

The takeaway: Be a detective, not a dictator

After over 15 years in this field, I can say that the greatest success comes not from blindly following the perfect plan, but from developing awareness. Instead of fixating on grams dès le premier jour, start keeping a journal. For food and for feelings. When are you full of energy? When do you feel sleepy in the afternoon? When are you stronger in the gym? When do you crave something specific?

After two or three months, you will start to see clear patterns. And then these small changes will come naturally. My #1 choice for a start? Begin with curiosity, not perfectionism. Your approach should be like a detective gathering clues about your own body, not like a dictator imposing commands on it. Start with one thing. Just one. For example, add 20g of dark chocolate and 10g of walnuts every afternoon in your luteal phase. And see what happens. That's all.

Note from Petar Mitkov

The biggest mistake I see ambitious female athletes make is applying nutritional and training principles created by and for men. Male physiology is relatively linear. Female physiology is cyclical by design. Treating your body the same way every day is like trying to plow black soil with a Ferrari – simply the wrong tool for the job. Understanding your own cycle is not just a "biohack." It's the most powerful map you have. It shows you when to hit the gas and when it's smarter to pull into the pit for tactical support.

Expert note from Sport Zona

In my practice with female athletes, I have seen how ignoring changes around the menstrual cycle can sabotage performance. Especially in strength sports, where strength and explosiveness are key, the right nutritional strategy can minimize the drop in strength that I often observe in about 60% of female competitors during the luteal phase. My observations show that focusing on sufficient protein intake and specific micronutrients like iron and magnesium during these periods often leads to fewer subjective complaints and more stable training results. This is individual, and for some women the influence is minimal, while for others it is dramatic.

Frequently asked questions

How do changing hormone levels during the menstrual cycle affect athletic performance?

Hormonal fluctuations affect metabolism, energy needs, and recovery ability. This means that nutrient and energy requirements can vary during different phases of the cycle.

What is 'nutrition and menstrual cycle' in sports?

This is a personalized approach where the diet is adapted according to the four phases of the menstrual cycle. The goal is to optimize athletic performance, reduce symptoms like PMS, and improve recovery.

Are there specific nutritional recommendations for the luteal phase of the cycle?

During the luteal phase, a slight increase in caloric intake (5-10%) and complex carbohydrate intake may be necessary. Adequate protein intake remains important, as progesterone can increase protein needs.

Which micronutrients are particularly important for female athletes in the context of the menstrual cycle?

Iron is key to managing losses during menstruation, while magnesium and B vitamins support energy metabolism and symptom reduction.