For many players, the gruelling conditions of the 2014 World Cup would have been the harshest they have ever been exposed to.
What's worse, as teams now reach the semi-finals, the likelihood of playing extra time while swimming in lactic acid becomes a real possibility. Therefore, it could be argued the team that wins the World Cup won't necessarily be the best, just the best at recovering.
But what are the coaching staff doing to ensure their players are recovering in time?
Are Belgium destined to step on to the pitch against Argentina with heavier legs after being taken to extra time by the USA or can cryogenic chamber therapy, used by France according to Metro, offer salvation?
Or how about the compression technology of Adidas and Nike—are there any recovery benefits to wearing a kit so tight it looks like it's been painted on? Studies reveal there could be and the team that embraces them might just stand a better chance of not only reaching the final but reaching it fully recovered.
Firstly, let's consider compression technology. Traditionally prescribed by doctors to reduce swelling and prevent circulatory problems such as deep vein thrombosis, the technology has since moved into the realms of sport as a means of accelerating recovery by reducing lactic acid and muscle stiffness.
But do they work and will a tight-fitting, Nike-branded compression sock really have Brazil running around like newborn spring lambs between matches?
Researchers from the School of Human Movement at Charles Sturt University in Australia think so. They wanted to test the effects of body compression garments on performance in cricket players.
So they had a group of 10 male athletes perform four randomised exercise sessions which involved repeatedly sprinting and throwing, both with and without compression clothing.
Interestingly, results revealed no significant difference in performance, heart rate or blood measures during exercise. However, 24 hours later, athletes did report lower post-exercise ratings of muscle soreness when wearing compression garments. Scientists concluded:
No benefit was noted when wearing compression garments for repeat-sprint or throwing performance; however, the use of the garments as a recovery tool, when worn after exercise, may be beneficial to reduce postexercise trauma and perceived muscle soreness.
It's an idea supported by sports scientists from Massey University in Auckland, New Zealand, who tested the benefits of compression technology on endurance runners during and after a 10-kilometer trial. Researchers stated that participants wore "knee-length compression stockings beneath ankle-length sports socks."
Similar to the Charles Sturt University study, they noted:
No performance or physiological differences were observed. But there was a reduction in delayed-onset muscle soreness 24 hours after exercise when wearing compression stockings.
But while compression technology is relatively cheap, can a team justify the cost of cryogenic chamber therapy such as the type Cristiano Ronaldo reportedly spent £36,000 on getting installed in his house according to Spanish paper El Mundo (in Spanish)?
Amazingly, if you look at research published in the journal of Sports Science, that £36,000 could just be worth it considering the potential benefits.
The therapy consists of exposure to very cold air that is maintained at -110 degrees Celsius to -140 degrees Celsius in special temperature-controlled cryochambers and it's believed:
The cold stimulation shows positive effects on the muscular enzymes creatine kinase and it should be considered a procedure that facilitates athletes' recovery.
The reason this is so significant is because creatine kinase is an enzyme found mainly in muscle tissue. Now, in a healthy athlete, there's typically only a small amount of creatine kinase found to be circulating through the body.
However, when an athlete is over trained and exhausted—highly likely in teams playing long into extra time—muscles become damaged and more creatine kinase is found in the blood.
Now, to quote research published in the Yale Journal of Biology of Medicine who analysed overtraining in elite endurance runners: "Elevation of creatine kinase in serum after exertion is a reliable marker of skeletal muscle injury."
So, if cryogenic chamber therapy shows "positive effects on the muscular enzymes creatine kinase," it's possible that the hefty £36,000 investment could yield a return in the form of a physiological athletic advantage and a World Cup trophy in the cabinet.
Whether this is the case remains to be seen—we'll find out on Sunday, July 13.
But based on the research contained within this article—as well as the musings of the article, "Could Match Fatigue Plague the 2014 World Cup in Brazil?"—the outcome of the 2014 World Cup could be influenced by science behind the scenes as much as skill on the pitch.