One of the more popular Russian innovations that is being used by many coaches today is block training. Some swear by it while others do not find it as effective as touted. Some even get the same results by using the standard programs.
The problem lies in not only how this block training is applied, but with whom it is used. Understand that block training is intended for high-level athletes. It is not for beginners or novices. For these latter athletes conventional periodization programs are best. To learn why this is so see Block Periodization.
Another aspect of block training that seems elusive is that the physical quality being gained is not united with the technical abilities of the athlete. Development of the physical quality should lead to improvement in skill execution. However, all too often, the physical quality such as strength is developed with no regard to technique.
The other problem that is most frequently encountered is that the level of the athlete is not commensurate with the block periodization. The block being used should be very specific to the athlete not only relation to his physical and technical abilities, but also to his level of mastery of the sport.
For more information on block training and periodization of different level athletes see Block Periodization and Secrets of Russian Sports Fitness and Training.