In study conducted by researchers at the University of Cordoba a link was found between moderate physical activity and improved hormone levels and sperm characteristics that improve overall reproduction according to a recent study published in the British Journal of Sports Medicine.
The purpose of the study was to evaluate the relationship of physical activity with sperm count and a total of 189 men participated in the study. They were asked to report the number of hours per week they spent exercising and watching TV, as well as provide a sample of their semen in order to analyze the quality.
The participants were also asked about any factors that could affect sperm quality, such as smoking, reproductive problems, diet and stress levels. The number of men with reproductive health problems was very low with only 25% smokers.
The number of hours spent doing moderate to vigorous intensity physical activity varied from 5 to 14 hours. The amount of time spent watching TV ranged from only 4 hours up to 20. The men who were more physically active tended to also eat healthier diets than those who were more sedentary.
Young men who live sedentary lifestyles and watch over 20 hours of TV per week were found to have nearly half the sperm count of people who don’t watch much TV. Men who watched more than 20 hours of TV had a sperm count 44% lower than men who watched the least.
On the other hand, men who did at least 15 hours of moderate exercise a week had very good quality sperm – their sperm count was found to be 73% higher than those who did little to no exercise. In fact, the results indicated that regardless of how frequent, light physical exercise didn’t make any difference to the sperm count. It is however noted that a low sperm count does not necessarily affect a man’s ability to have children though the study does, however, reveal that lots of physical activity may actually improve semen quality.
Sperm quality parameters
According to the ‘Manual for the examination of human semen and semen-cervical mucus interaction’ published in 2010 by the World Health Organisation (WHO), the most frequently examined parameters in a seminogram for evaluating semen quality are:
- Liquefaction: 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.
- Viscosity: If the sample is very viscous, this could be down to a prostate dysfunction.
- Volume: The normal volume of an ejaculate after 3 to 5 days of abstinence is approximately 1.5 ml. A lower value is called hypospermia.
- Colour: Semen is normally an opalescent, slightly yellow colour. When colour is slightly different, the possible cause should be studied.
- pH: This value should be above 7.1. Lower values could be a sign of azoospermia (absence of spermatozoids) or chronic inflammatory processes.
- Spermatozoid concentration: 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.
- Motility: 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.
- Vitality: The percentage of living spermatozoids should exceed 58%. Any lower and this is called necrozoospermia.
- Morphology: 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.
- Leukocytes: 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.