This is a guide for women who practice sport that was written by popular demand. I will explain how to improve the performance as well as the physical condition of women.
- 1 Energy expenditure depending on the exercise in women
- 2 Use of the intramuscular triglycerides
- 3 Weightlifting in women
- 4 High intensity training in women
- 5 Consumption of proteins in women
- 6 Calories intake in women
- 7 Common mistakes in diet of women
- 8 What is the main symptom of an extreme caloric deficit?
- 9 How much carbs should a woman consume?
- 10 What happens with fat?
- 11 And what happens with proteins?
- 12 Sportswomen
- 13 Example of a Diet for a sportswoman
- 14 Bonus: Muscle gain in women
- 15 Conclusions
- 16 Sources
Energy expenditure depending on the exercise in women
Even though there are many differences between both sexes, we are going to focus on those that have an impact at a hormonal and metabolic level. If you have been reading my articles, you probably know that the use of fats or carbohydrates by the cells will mainly depend on the intensity of the exercise. So, as the intensity of the exercise increases, the use of glucose as energy source will increase, and it will be enhanced depending on the sex.
Women, use more fat as an energy source when they are at rest2, but they use more glucose when they are given a pre-workout1
- higher testosterone in men3, and
- a higher amount of IMTG in women.
Testosterone plays a very important role when it comes to gaining muscle, since once the boys go through the puberty, there is an increase of muscle mass, which coincides with higher levels of said hormone4.
Use of the intramuscular triglycerides
The intramuscular triglycerides (IMTG) are little energy reserves that are found in the muscles. Studies have proven that these “fats” are higher in women than men, which helps to meet the energy demands during the workout5.
These intramuscular triglycerides will be mainly found in type I fibers, which are oxidative fibers, which will maintain the performance during long workouts6
Weightlifting in women
When it comes to weightlifting, regardless of the level of workout, men undergo a drop of muscle glycogen in both types of muscle fibers, something that did not happen in women8. This is due to the fact that women meet their energy demands in moderate intensities through the metabolism of fats, as we saw previously.
But, what happens when we talk about intense workouts?
High intensity training in women
The same thing happens again, more or less. The lactate levels are a 22% lower in women than in men9.
For those who do not know about this, lactate is a marker that indicates that we are performing a high intensity workout. When the presence of oxygen is very low or the requirement is high, the body produces energy from glucose, which generates lactate
Consumption of proteins in women
This can be a critical point for women, since the current advise for female athletes is far from what truly happens, since only a 26% of women consume the adequate amount of protein10.
A low consumption of protein will result in a worse muscle recovery, a lower synthesis of protein that will result in a greater loss of muscle as well as a higher sensation of hunger
Calories intake in women
In order to understand the nutrition of a sportsperson, we need to think about the pressure that they undergo due to their physical appearance, since the number of cases of anorexia are increasing due to advertisements and the tinier sizes in clothing. This will influence the caloric intake, and in the case of female elite ice skaters, a 30% of them believe that are overweight12.
The consequence of a poor caloric intake is a deficiency of vitamin D, E, calcium, magnesium, phosphorus, etc. These excessive caloric deficits slow down our metabolism, activates obesogenic mechanisms that will make it easier to gain body fat13.
Common mistakes in diet of women
My experience on this field is that most of the girls that prepare for Bikini contests or a photo session, follow very poor diets.
A part of the fitness coaches (and by these I am not trying to blame every single one of them) advises diets that range between 800-1200kcal with a very low supply of carbohydrates and which tend to avoid them after certain times.
What is the main symptom of an extreme caloric deficit?
Amenorrhea. Up to a 50% of women who do exercise experience changes in their menstrual cycle15.
There are different factors that affect this state, like a very low fat intake, a very low caloric intake, psychological stress (higher levels of cortisol) or metabolic stress due to overexercising.
If we think about it, a sportswoman will meet at least 2 of these factors. Along with amenorrhea, we can observe other side effects like lower levels of T4, which will result in a worse transformation to T3, which will result in:
- a slower metabolism,
- tiredness, or even
How much carbs should a woman consume?
This is one of the questions that many women tend to ask and the issue that we talk less about. If you remember, at the beginning of this guide, I spoke about how women used less glucose as an energy source and they resynthesize less post-workout glycogen, in fact, some studies show how after 4 days following a diet high in carbs, the amount of muscular glycogen did not change17.
Graphic adapted from Mark A. Tarnopolsky et al 2001
This worse use of the carbohydrates as an energy source and the worse recharge of glycogen is going to affect the type of carbohydrates that we are going to choose for women.
In my own opinion, sportswomen tend to base their source of carbohydrates in non-refined carbohydrates, because when they have to reduce the amount of carbs, they tend to prioritize those foods that are high in fiber.
With this intake of carbohydrates, the use of refined carbs becomes a very valuable tool. This intake would imply a 90% of the required calories in the case of women, which is kind of crazy. In my opinion, I believe that a consumption of around 3g per kg of body weight is a correct amount, in this way, a female athlete that weights 65kg should consume around 195g of carbohydrates.
What happens with fat?
Knowing that women use more fat as a source of energy, the role of this macronutrient becomes more important. A curious fact, which I probably have mentioned more than once, is that as we transition from a sedentary lifestyle to a normal-high training level, our body goes from oxidizing carbs to oxidize more fat, which means that those women who have been training for several years have a perfect fat metabolism.
Now that we know how women use more fat during the workout through the IMTG (intramuscular triglycerides), we have need to consider if a diet that is high in carbs is the best way to refill these “reserves”:
High Carbs Diet VS Moderate Fat Diet
For this, a study compared how a high carbs diet (10% of the energy came from fats) or a moderate diet (35% came from fats) affected the recovery of sportswomen19. The IMTG reserves were replenished with the moderate fat diet after 22h, while the high carbs diet could not do so even after 70h, which reflects the importance of a high fat diet in sportswomen.
The higher the use of IMLC, the longer the distance. Adapted from Enette Larson-Meye et al 2002.
Even though the use of the intramyocellular lipids reserves depends on the intensity and duration (spending a 70% if the exercise lasts more than 2h), few women recharge their deposits due to the fear of consuming too many calories and increasing their fat percentage.
The best thing would be to consume around a 35-40% of the calories as fat20, specially those that are mono and polyunsaturated, which helps to increase the lean body mass tissue (LBM), and saturated fats, like the one from coconut.
And what happens with proteins?
As you may imagine, the protein requirements change between men and women, in the first case the requirements are much higher, since the synthesis of proteins is higher for them. On the contrary, the protein breakdown is lower in women21.
The reason why they undergo a lower protein breakdown is because women use more fats and less carbs during the workout, as we have previously highlighted, even though it can be due to a dimorphism on the beta receptors (a point that I will develop in the feature).
This does not mean that women do not have a negative nitrogen balance after the training, or that they do not need to take a post-workout protein shake, on the contrary, women who perform a high muscle contraction (in the case of weightlifting) can benefit from a serving after the workout.
To sum up, we can observe that sportswomen:
- Use more fat as a source of energy, which allows to save more muscle glycogen
- Lower protein breakdown during the workout, which will affect the amount of protein that we need to consume
- More difficulty to gain muscle mass, which will influence the type of workout.
- Different hormone environment, which will affect the ability to lose body fat.
Now that we have reached this point, here is the most difficult part:
Which foods follow the previous premises?
Example of a Diet for a sportswoman
Let’s imagine a woman that practices CrossFit:
- She wants to lose fat without losing performance.
- She performs 2 workout sessions, one soft cardio session on an empty stomach and a box workout in the evening.
The diet would be as follows:
|Pre-Workout: Synephrine + Caffeine|
|Post-Workout: 20g of chocolate EVOWHEY pancakes, egg whites, 2 ripe bananas with jam, and a bunch of nuts|
|Mid-morning: Roasted broccoli with garlic, salt, and olive oil + a roasted salmon fillet + one portion of fruit|
|Lunch: Spinach Omelette (depending on the amount of protein) with a sliced sweet potato. Dessert: Fruit salad with whipped cheese and honey|
|Post-Workout (Dinner): A salad with tomato, grilled carrot, olives, walnuts, sliced chicken with spices|
In this way, we will guarantee:
- a proper “timing”,
- more metabolic flexibility, and
- a better recovery.
Bonus: Muscle gain in women
This is probably one of the points that tend to be more interesting for women and which has one of the simplest answers. If you remember properly, I spoke about muscle mass in an article, and I said that there has to be a positive nitrogen balance in order to gain muscle, in other words, there has to be more protein synthesis than breakdown.
We know that women undergo a lower breakdown and synthesis of protein, which means that we need to increase the second one to create an “ideal” environment.
The best way to achieve this is through intense weightlifting, there is no other way. Even though many tend to fear looking to muscular this will not happen due to the high estrogen levels. Estrogens a female sex hormone that controls a great part of the energy metabolism, weight, and distribution of fat.
Thanks to this hormone, women are more sensitive to insulin and, therefore, their chances of suffering diabetes is lower. Weightlifting is quite interesting since it allows to consume more carbs/calories in the diet, since it avoids the harmful effects of hyperinsulinemia23.
To conclude, we must take advantage of that higher sensibility to insulin that women possess in order to make little carbohydrates loading during some of the training days, and in this way achieve a caloric excess without having a negative impact in our body fat, because when the muscle is sensitive to insulin/glucose, our adipocytes will barely absorb the glucose.
With this, I say goodbye, hoping that you enjoy this guide as much as I have enjoyed writing it.
- Substrate utilization during exercise performed with and without glucose ingestion in female and male endurance trained athletes.
Riddell MC1, Partington SL, Stupka N, Armstrong D, Rennie C, Tarnopolsky MA.
- Substrate utilization during endurance exercise in men and women after endurance training.Carter SL1, Rennie C, Tarnopolsky MA.
- Endocrine regulation of exercise substrate utilization in women compared to men.Braun B1, Horton T.
- Gender differences in protein metabolism.Tipton KD1.
- Myocellular triacylglycerol breakdown in females but not in males during exercise. Steffensen CH1, Roepstorff C, Madsen M, Kiens B.
- Fiber type composition of the vastus lateralis muscle of young men and women.Staron RS1, Hagerman FC, Hikida RS, Murray TF, Hostler DP, Crill MT, Ragg KE, Toma K.
- Intramuscular substrate utilization during prolonged exercise. Essén B.
- Muscle fiber-specific glycogen utilization in strengthtrained males and females.Bell DG1, Jacobs I.
- Metabolic response in type I and type II muscle fibers during a 30-s cycle sprint in men and women. Esbjörnsson-Liljedahl M1, Sundberg CJ, Norman B, Jansson E.
- Nutrient intakes and dietary behaviors of male and female collegiate athletes.Hinton PS1, Sanford TC, Davidson MM, Yakushko OF, Beck NC.
- Protein and amino acids for athletes.Tipton KD1, Wolfe RR.
- Food preferences, dieting behaviors, and body image perceptions of elite figure skaters. Jonnalagadda SS 1 , Ziegler PJ , Nelson JA
- Metabolic adaptation to weight loss: implications for the athlete.Eric T Trexler1, Abbie E Smith-Ryan1* and Layne E Norton
- Relationship between energy deficits and body composition in elite female gymnasts and runners.Deutz RC1, Benardot D, Martin DE, Cody MM.
- Eating behaviors, nutritional status, and menstrual function in elite female adolescent volleyball players. Beals KA1.
- Thyroid hormone concentrations and muscle metabolism in amenorrheic and eumenorrheic athletes.Harber VJ1, Petersen SR, Chilibeck PD.
- Carbohydrate loading and metabolism during exercise in men and women.Tarnopolsky MA1, Atkinson SA, Phillips SM, MacDougall JD.
- Gender differences in carbohydrate loading are related to energy intake.Tarnopolsky MA
- Influence of endurance running and recovery diet on intramyocellular lipid content in women: a 1H NMR study.D. Enette Larson-Meyer
- Effect of diet on the replenishment of intramyocellular lipids after exercise.Décombaz J1, Fleith M, Hoppeler H, Kreis R, Boesch C.
- Gender differences in the regulation of amino acid metabolism. Lamont LS1, McCullough AJ, Kalhan SC.
- Effect of glycogen availability on human skeletal muscle protein turnover during exercise and recovery
- Gender differences in insulin action after a single bout of exercise. Perreault L1, Lavely JM, Bergman BC, Horton TJ.
- Capillary supply of the quadriceps femoris muscle of man: adaptive response to exercise. Per Andersen and Jan Henriksson
- Mechanism of enhanced insulin sensitivity in athletes. Increased blood flow, muscle glucose transport protein (GLUT-4) concentration, and glycogen synthase activity.