Exercise physiology and Exercise testing Mitochondrial DNA and Maximun Oxygen Consumption
Index • Introduction about this article • General information • 1º investigation • 2º investigation • 3º investigation • 4º investigation • Author’s opinion • Final conclusion
Introduction about this article • This article is about relationship • between mitochondrial DNA • and maximum oxygen consumption. • 2. There are four different investigations. • 3. The early researchers addressing • the contribution of inheritance.
General information DNA: Deoxyribonucleic acid (DNA) is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms and some viruses. The main role of DNA molecules is the long-term storage of information Different individual have different DNA sequence. Morphs may account for some of the differences including VO2 max.
General information Dna mitochondrial: (mtDNA) is the DNA located in organelles called mitochondria. • Determinants of Maximal Oxygen Consumption: • Cardiac output • The oxygen carrying capacity of the blood • The amount of exercising skeletal • muscle and the ability of muscle to utilize supplied oxygen
1º investigation Authors: Dionne et al. Aim: Association between mitochondrial DNA sequences and aerobic performance. Also they assessed the relationship of baseline VO2 max and the response to training. Process: Endurance-training program during 20 week. Subject: 46 North Americans who were sedentary. Results: The subjects had a morph in the gene encoding Subunit 5 of NADH dehydrogenase. Conclusion: Relationship to the training responses of VO2 max.
2º investigation Authors: Rivera and colleagues Aim: Measure the frequency of each of the three morph identified within the NADH dehydrogenase and of one morph of the D-loop. Subject: 125 elite endurance athletes and 65 sedentary. Results: Don’t found difference in the frequency of these morph between groups
3º investigation Authors:Chen et al, Ma et al. Aim:A researches focused on the D-loop, which contains factors that the modulate mithocondrial DNA replications and transcription. Subject:A sample of 120 Chinese subjects: 67 elite endurance athletes, 33 general endurance athletes, and 20 sedentary. Results: There were nine morphs, and their frequencies were significantly different between three groups. Conclusions: This apparent association between mithocondrial DNA D-loop polymorphism and endurance capacity needs confirmation. The authors suggested that a better relationship might exist between the mithocondrial DNA morphs endurance performance rather than VO2max.
4º investigation Authors: Melton et al. Aim: Relationship between mitochondrial DNA D-loop morphs and VO2max. Subjects: 40 well-trained Australian male endurance cyclists. Results: There wasn’t association between VO2max and the D-loop morphs in this population of athletes.
Author’s opinion The autors are in agreement with reports of Dionne et al. (1991) and Rivera et al. (1998), who found no significant relationship between D-loop morphs and either sedentary VO2max or elite endurance athlete status. The discrepancy between these findings and those of Chen et al. (2000) and Ma et al. (2000) may be related to the ethnic differences between the subjects and the small sample sizes do not allow firm conclusions about the presence or absence of small effects.
Final conclusion There is evidence that V02max in athletes is limited by the ability to deliver oxygen to the muscles, rather than the ability of muscles. However, mithocondrial function could still be closely related to the trainability of VO2max in previously sedentary population and sub-VO2maximal endurance performance in athletes.
JOSE MIGUEL PERUJO FRIAS PEDRO ALONSO TEJERO SANTANA THANK’S FOR YOUR ATTENTION