A new study has linked moderate physical activity with sperm characteristics that "favour reproduction".
According to researchers from the University of Cordoba in Spain, sperm quality deteriorates in men who have sedentary lifestyles.
The study suggests that men who do moderate physical exercise have better hormone levels and healthier spermatological processes.
"We analysed qualitative semen parameters like the ejaculated volume, sperm count, mobility and sperm morphology," explained the lead author of the study Diana Vaamonde in a statement.
Exercising more (61%)
Drinking more water (49%)
Cut back on socialising (23%)
Given up alcohol (18%)
Removing certain foods (such as red meat) out of diet (18%)
Cut out caffeine (15%)
Stopped wearing tight underpants (15%)
Give up smoking (13%)
Having less sex (13%)
Cut back on work to reduce stress (11%)
Semen quality at large has dropped in the last 50 years, due to exposure to external agents, as well as alcohol and tobacco consumption, which has caused an increase in reproductive problems.
"Despite the fact that the sample population is not very big (31 men), given the complexity of the analysis, this is the first study that assessed the differences between these parameters in both populations," states the researcher.
The results conclude that the physically active subjects display better semen values and that moderate exercise is the key.
After ejaculation the semen coagulates and needs to be liquefied for its study. Under normal conditions the semen stays liquefied for a total of 60 minutes after ejaculation.
If the sample is very viscous, this could be down to a prostate dysfunction.
The normal volume of an ejaculate after 3 to 5 days of abstinence is approximately 1.5 ml. A lower value is called hypospermia
Semen is normally an opalescent, slightly yellow colour. When colour is slightly different, the possible cause should be studied.
This value should be above 7.1. Lower values could be a sign of azoospermia (absence of spermatozoids) or chronic inflammatory processes.
The normal value is 15 million for each ml of ejaculate or 39 million in the entire sample. If these values are not reached, this is a case of oligozoospermia.
The percentage of mobile spermatozoids and those with progressive motility (those that are mobile yet travel) is assessed. Motility is considered normal when at least 32% of spermatozoids have progressive motility. If not, this is called astenozoospermia.
The percentage of living spermatozoids should exceed 58%. Any lower and this is called necrozoospermia.
Examples can be seen of both normal spermatozoids and those with different abnormalities, whether in the head or the tail. Semen considered normal should have 4% or more of normal spermatozoids. Cases in which this value is lower are called teratozoospermia.
If leukocyte concentration is higher than 1 million per ml of sample, this could indicate an infection (leukocytosis).
Antisperm antibodies or Mar test
This reflects the quantities of spermatozoids joined to other cells or particles. If more than 50% of spermatozoids are found joined in this way, this could suggest an immune problem.
In 2010, the same researchers published a study showing that the sperm parameters of elite sportsmen (triathletes and waterpolo players) are worse than men who are just physically active.
It is possible that the increased strain of training causes a decline in sperm quality.
"Despite that fact that more studies are needed to confirm these findings, we can suggest exercise to improve the hormonal environment and stimulate the sperm process," says Vaamonde.
The new research is published in the European Journal of Applied Physiology.