Differences between men and women in sports

Examining Differences between men and women
Source: https://mtintegraal.nl/artikelen/310/verschillen-tussen-mannen-en-vrouwen-onder-de-loep (translated to English)

There are visible but also less visible differences between men and women. The visible differences are partly responsible for the differences in physical performance. The less visible differences are most interesting for explaining uneven performance in all forms of sports: strength sports, sports where speed is decisive and endurance sports, where endurance counts heavily. These differences do not only play a role in sport; also for performing work in the so-called heavy professions ( o.a police, fire brigade, armed forces ) have consequences for the physical differences between men and women.
Anthropometry and muscle strength
Women are lighter ( 20-25% ) and shorter ( 10 to 12 cm ) than men. Men are about 15% fat tissue, women have about 25% fat tissue. Men have 40-45% muscle tissue, women 25-35%. Differences in length and muscle mass affect the muscle strength that can be delivered [ 1 ].

Static muscle strength
There is a relationship between height and maximum static force: the force exerted without the muscle lengthening or shortening. When corrected for height, the mean strength of adult women is ± 80% of that of men [ 1 ].

The differences become smaller when the force is expressed per kilogram body weight and even smaller when the percentage of fat is taken into account. When the force is expressed per cm2 of muscle cross section, the power differences disappear: per cm2 of muscle cross section, 3-6 kilograms of force can be applied [ 2 ]. In practice, however, it usually concerns the total amount of force that can be delivered.



Slow and fast muscle fibers
A muscle consists of slow and fast muscle fibers. The slow ( slow twitch, ST ) are mainly used during endurance effort and the fast ( fast twitch, FT ) during short and very short duration effort, such as the hundred meter sprint. The cross-section of the ST fibers in the woman is about 70% of that in the man and of the FT fibers about 85%. On average you can say that the muscle cross section of the M. gastrocnemius ( calf muscle ) of the woman is about 75% of that of the man [ 3 ]. Since there is a linear relationship between muscle cross-section and maximum static force, it can also be concluded on this basis that the maximum static force of women is less than that of men.



Dynamic muscle strength
In addition to the maximum static force, the dynamic force ( in sports such as weight lifting and rowing ) is important in many sports. The magnitude of the dynamic force that a person can supply depends largely on the maximum static force and so the maximum dynamic force of women is also smaller than that of men.



Arm strength vs. leg strength
In general, it can be said that the strength of women is about 2/3 that of men. There are differences per muscle group. Most striking is the difference between arm and leg strength. Where the maximum muscle strength of the arms in women is half that of men, the difference in muscle strength of the legs between men and women is much smaller ( 25-35%) [ 1 ].
Incidentally, it appears that in women the percentage of ST fibers in the leg muscles is greater than the percentage of FT fibers. Therefore, women seem to be better equipped to deliver endurance performance than to make short-term effort [ 4 ].

Testosterone
In addition to the above-mentioned causes for the differences in strength between men and women, the influence of the male sex hormone must be called testosterone. Testosterone has a protein-building effect and since muscles are made up of proteins, someone with more testosterone ( men ) is more muscular than someone with less testosterone ( women ). The larger muscle cross section is directly due to the amount of testosterone. For women, as for men, it is possible to increase muscle strength through training, but women will never be able to reach the strength level of men.

Speed and energy
In addition to strength, speed is a performance-defining factor in sports such as long jump, the hundred meter sprint and other cyclic forms of movement in which large accelerations occur in the movement for a short time. This speed depends on the strength and so the speed of female top athletes is also smaller than that of male top athletes. In addition, women have relatively shorter legs than men, which is also a disadvantage in this type of sport.



ATP and CP

During the first seconds of exercise, energy is released from the stock ATP ( adenosine triphosphate ) and CP ( creatine phosphate ) in the muscle tissue. Women have less muscle tissue than men and therefore have a lesser amount of ATP and CP. This also puts women at a disadvantage in so-called speed sports [ 2 ].

Duration performance
Decisive for delivering endurance performance is high stamina. In physiological terms one speaks of a high aerobic power or a high maximum oxygen uptake ( VO2max ). In order to perform well with a long-term effort, one must be able to perform at about 80 percent of the VO2max work for a long time. The heart and ( the composition of ) the blood play an important role in this [ 1 ].

Circulation
Women have a smaller heart ( 210 grams ) than men ( 300 grams ) which allows a man to pump out more blood per heartbeat than a woman. The amount of blood pumped around per resin stroke is the stroke volume ( SV ). A woman's SV is ± 94% of a man's stroke volume.



The cardiac output ( HMV; amount of blood pumping out the heart per half ( left and right ) and per minute ) is determined by the product of heart rate ( HF ) and SV. To achieve the same HMV as a man, the woman's heart rate is always higher than that of a man [ 2 ]. The same external load is therefore heavier for a woman than for a man because she needs a higher HF for this. Expensive training increases the heart and as a result the SV increases, even in women, but the differences between men and women persist. The maximum heart rate ( HR max ) of men and women is the same.


Men have 5 to 6 liters of blood and women about 4.5 liters. The red blood cell concentration ( erythrocytes ) is higher in men than in women. The erythrocytes contain hemoglobin, a protein through which the blood is able to bind oxygen. In a woman, less oxygen is bound to blood because she has less hemoglobin than men.



The lower stroke volume and the lower amount of hemoglobin mean that less oxygen can be transported to the working muscles in the woman, per unit time. There are also some differences in breathing variables, but they do not play a significant role in this [ 1 ]

Energy and oxygenation
Energy must be released in order to deliver labor. With very short-term effort, the energy is released without oxygen. One speaks of anaerobic energy supply. With effort that lasts longer than one to two minutes, the share of the energy supply in which oxygen is involved increases. One speaks of aerobic energy supply.



 The enzyme phosphofruktokinase ( PFC ) plays an important role in the anaerobic energy supply and the enzyme succinate dehydrogenase ( SDH ) is an important role in the aerobic energy supply. It appears that the activity of these enzymes in women is lower than in men. This means that women can release less energy than men.



The lower enzyme activity combined with the lower oxygen transport capacity means a disadvantage to the man during duration effort for the woman. Incidentally, there are indications that in women the ratio between the activity of the two enzymes ( SDH / PFC ) is such that women have relatively greater potential for aerobic energy supply. In other words, women are more suitable for endurance effort than for short-term effort [ 4 ].



Maximum oxygen uptake

All the above factors related to aerobic energy supply result in a lower aerobic capacity ( VO2max ) of women compared to men in comparable training state. This applies to the absolute VO2max ( liter O2 per minute ) as well as to the relative VO2max, taking into account the body weight ( ml O2 per minute per kilogram body weight ).



This implies that women are at a disadvantage in sports where stamina is used. The relative VO2max is important in activities where body weight has to be moved, such as walking and cycling [ 1 ].

Sports performance
The ability to complete endurance sports is often hindered by fatigue. The ‘ man with the hammer ’ strikes. The most likely cause of this is depletion of the carbohydrate supply, or glycogen depletion. A possible solution to postpone its occurrence is to use a different energy source. Well-trained endurance athletes get more energy from the fatty acid reserve than less well-trained endurance athletes. Research shows that women are better able to get more energy from fats than men. The female sex hormone estradiol appears to be responsible for this [ 5 ].

Performance differences
The performance differences between men and women are narrowing and some even claim that women are catching up with men. Serious sports by women, however, only got off the ground late and generally accepted. This has enabled women to benefit from all developments in the areas of nutrition, training schedules and footwear at an accelerated pace. This has been more gradual in men. Due to the unavoidable physical differences between men and women, it is likely that the performance in top sport provided by women will never exceed that of men.

Heavy professions and tax
There are more and more serious professions in which women work in addition to men. Think of the police and the fire brigade, but a woman is no longer an exception within the armed forces. However, due to the physical differences between men and women, certain tasks are relatively more difficult for women than for men. Oxygen uptake ( VO2 ) and slightly less heart rate ( HF ) provide an accurate estimate of the energetic load. At the same load, women have a higher heart rate than men. We have seen above that this has to do with differences in the size of the heart. In addition, at a load that requires a certain amount of oxygen, women are at a higher percentage of their VO2max than men. This is due to the fact that men's VO2max is greater than that of women.



Determine tax

Incidentally, it is better to speak of% and% respectively for both the calculation of the load on the basis of the heart rate and the calculation of the load on the basis of the oxygen uptake % maximum heart rate (% Hfmax ) or% of the maximum oxygen uptake (% VO2max ). It is even better to work with% heart rate reserve (% HRR ) instead of% Hfmax. In the case of% Hfmax and% VO2max, the individual maximum HFmax or VO2max are involved in the determination of the load. In addition,% HRR involves the individual resting heart rate ( HFrust ) [ 6 ]. When the tax is presented in this way, it is possible to objectively compare the burden on different employees, and therefore also the burden on men and women, during various activities.



When using% HFmax,% VO2max and% HRR, it is important that the individual values for HFrust, HRmax and VO2max are measured and not estimated using in vogue formulas, as is often the case.

Finally
The above story is about the “ average man and woman ”. There are women who 'score' higher / better than men on the mentioned parameters. And so there are women who outclass men on the sports field and there are women who are suitable for heavy professions, while some men are not.


[ 1 ] PO Åstrand et al, Textbook of work physiology, 4th ed., Human Kinetics, 2003

[ 2 ] WD McArdle et al, Exercise physiology: energy, nutrition & human performance, 6th ed., Lippincott Williams & Wilkins, 2007

[ 3 ] DL Costill et al, Skeletal muscle enzymes and fiber composition in male and female track athletes, J App Physiol, 1976, vol 40, pp 149-154

[ 4 ] E Nygaard, Skeletal muscle fiber characteristics in young women, Acta Physiol Scand, 1981, vol 112, pp 299-304

[ 5 ] L Isacco et al L, Influence of hormonal status on substrate utilization at rest and during exercise in the female population, Sports Med, 2012, vol 42, pp327-342

[ 6 ] M Karvonen et al, The effects of training on heart rate. A longitudinal study, Am Med Exp Biol Fenn, 1957, vol 35, pp 307-315