For speed, increasing speed, I would have thought so yes. Michael Johnson was there conducting the training at the summer camps. The players I refer too where already fast players, they just wanted to become even faster. But regardless…
I’m still far from convinced there is such thing as optimal training for soccer & I’ve been playing for the best part of a decade.
Charlie said it best…
Physical fitness/conditioning will come mainly from game time, making runs, shutting down players, stop start, stop start running in the actual game…
This tempo stuff at 75% max Speed, 20-25 seconds efforts over 150 yards, should we increase it to 80%?.
I work much harder during games than training. I train hard, but I dig in even harder during a game, crowd/adrenaline/urging from the manager etc & tempo stuff at 75% max Speed goes clean out of the window. If I want too be making darting runs in the 85th minute, I better be making darting runs in the 85th minute in all my previous games. Basic match fitness.
There is a lot of underestimating of players on these boards. There are some very good athletes in Europe, players with good speed, good stamina if there position calls for it & more often than not, players have enough in the bank physically to do the job that is asked of them.