College Dude - you are right. I don't know hom much does Adam exactly do, but I am sure it is less then 120-130km/week in the peak mileage. On the other side, Marcin may be at about 150km/week in the peak mileage. The yearly average may be like 80-90km/week for Adam and 100-120 for Marcin.
But of course Marcin does some dynamic exercises and plyos too. And Adam does some tempo runs, like 6km progressing from 3:25 to 3:00/km. And both of them do a lot of general strenght and core. So, there are the differences but similarities too. It is natural, because Adam is more 400/800 and Marcin 800/1500.
The main difference is training from the lactate point of view. Marcin is the low lactate runner, in training and competitions. And Adam is the opposite - high lactate. My training was more high lactate, like Adam - so sometimes I used to run 5 days a week with lactate between 10 and 25 mmol. Plyos, tempo runs, repetitions - I could finish everything with high lactate. At 15mmol I was feeling easy ; ) And so is Adam - he can easily go in repetitions (say: 3x400m in 52-50s) for lactate like 25mmol.
Marcin is different - even in competition it is impossible for him to have more than 12-15mmol. His training is mostly under 4mmoles.
Polish coaches use lactate devices very often. So, sometimes not the type of training is important, but the lactate response. Pawel Czapiewski used to do some very hard power sessions like jumping, skipping and bounding uphill with lactate about 20mmol and more.
But Pawel Czapiewski always was a typical 800m type. Not the 400/800, not 800/1500, just 800m. Not so good speed and average endurance, but that mix produced the 1:43,22. So - every polish top 800m runner is a little bit different and the training is different too.
What is interesting - we have pretty good 400m runners. Few years ago our national 4x400m relay competed well against Americans. So it may be, that our training (and maybe genes?) are best for distances like 400/800m.