The results of studies indicate that blood donation can have short-term impact on reduction of the exercise tolerance in the wide range of endurance activities.
The aim of the research conducted by a team of scientists from the University of Aberystwyth (Wales) was to assess the impact of blood donation (in the amount of approx. 450 ml) for a change of exercise tolerance and size of VO2ma among young (23 years ± 6 years) healthy individuals (10 men and 1 woman have been studied).
The studied individuals were asked to perform several tests on a cycle ergometer to measure the maximal oxygen consumption (VO2max), gas exchange threshold (GET, gas exchange threshold) and exercise tolerance before and after 24 hours from the time of blood donation. blood donation and exercise
Measurements of VO2max and GET were made during a graded exercise test with an increase in load of 30 Watt every minute, and pedaling rhythm of 90 revolutions/min.
Individual exercise tolerance was determined by the time the subjects were able to continue the effort with an intensity equal to 80% of the difference between the intensity at GET and VO2max (defined as high intensity).
Obtained results of the studies have shown that as a result of blood donation there was an reduction of hemoglobin concentration (an average from 15.4 to 14.7 g/dl) and hematocrit level (an average from 44 to 41%).
It was also reported that there was a reduction in the level of VO2max (on average from 3.79 to 3.64 l/min) and the reduction of exercise tolerance among studied individuals (average time to exhaution has been reduced from 375 to 321 seconds). Blood donation and effort
The authors concluded that after 24 hours from the time of blood donation there appear to be a reduction in the level of VO2max and exercise tolerance of intense physical efforts among young people.
Burnley M., Roberts C. L., Thatcher R. et al., Infuence of blood donation on O2 uptake on-kinetics, peak O2 uptake and time to exhaustion during severe-intensity cycle exercise in humans. Experimental Physiology, 2006; 91: 499–509. blood donation and exercise