For some decades now, stretching has been considered a fundamental practice for improving basic musculoskeletal fitness, trauma prevention and muscle rehabilitation, as well as optimizing athletic performance in various disciplines.
Precisely in relation to this last area, it is necessary to remember that the opinions of sports technicians are often discordant, which is why scientific research has tried to clarify its true entity.
In fact, while stretching boasts many advantages, it can also compromise the development of maximum strength. Obviously, this happens only in particular conditions, ie when the protocol is performed immediately before the performance (not after) and with elongation times equal to or greater than one minute (not less).
But what about aerobic endurance?
A 2010 study entitled " Effects of static stretching on energy cost and running endurance performance " also sought to respond to this technical methodological uncertainty.
The effects of static stretching on energy costs and endurance sports performance in well-trained male runners were examined.
10 men practicing cross-country running, aged between 25 +/- 7 years, with an average of VO2max of 63.8 +/- 2.8 ml / kg / min were recruited.
The exams were carried out in the laboratory and on 3 separate days. On day 1, anthropometry and VO2max were evaluated; on days 2 and 3 (sessions spaced by a week), participants (chosen at random) performed a 60-minute treadmill test with or without preparation stretching.
The stretching was static, it included 5 exercises (of the main muscle groups belonging to the lower body district) and lasted 16 minutes; the group that did not stretch was at rest.
The run protocol consisted of running 30 minutes at 65% of VO2max (pre load), followed by 30 minutes of performance in which the participants had to run as far as possible without displaying distance and speed.
The pre-load was evaluated through caloric expenditure, while the performance was assessed by measuring the distance traveled.
The performances were significantly higher in the group that did not perform the stretching (6.0 +/- 1.1 km) compared to the group that carried out the elongation protocol (5.8 +/- 1.0km), with an expenditure significantly more energetic in the stretching group than the set that remained at rest (425 +/- 50 vs 405 +/- 50kcal).
The results suggest that stretching before a strong running performance can reduce performance and increase the total energy cost.
