I mentioned in the Big Cubes Summer thread that I might post a thread on some things I've learned for preparing big cubes BLD before a tournament. I feel what I have to say fits perfectly well in this thread though, so I'll post here.
Some things I learned for practicing, and training, big cubes BLD.
1) not doing solves for a week or two before the competition for 4x4x4 BLD doesn't seem to hurt your times. In fact, I tend to get faster times when I do this. I don't know how to account for the fact that I might just be a bit further along the learning curve, but I tend to get fast times on 4x4x4 if I don't practice 4x4x4 shortly before the competition.
2) Not practicing 5x5x5 BLD before the competition is a very bad idea. I remember Mike mentioned he did something like 5-6 solves on 5x5x5 BLD before the Virginia Open, which led to him not only getting a success but also a fast time for him at that time. I don't know if I will take it to that extreme, but I have found that when I don't practice 5x5x5 shortly before a competition I tend to DNF at the competition.
3) Practice your memory methods. I practiced my memory images/words/journeys for about 2 solid weeks before Big Cubes Summer, and I felt that my memory was good overall throughout the competition. I did have one significant recall delay (60+ seconds) on my second 5x5x5 BLD solve, but other than that I had no recall delays and fairly fast memo for me.
4) Exercise! This is so very, very important. I have been using exercise in my competitions now for BLD events, and Daniel and I discussed a possible best way to utilize this during a competition. I over exercised shortly before my 4x4x4 BLD solve at Horizons, and I think this partially contributed to my DNF there. During memo I was sweating like crazy and my heart was still pounding. Ever since Decatur Open I have been using exercise to help me focus, and so far I like the results of it a lot.
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Here is how Daniel and I exercised on the day of at Big Cubes Summer, and my thoughts on how it went. I feel this type of routine is very effective compared to what I have done before this competition.
1) Stretch in the morning, then do a workout routine until you break a sweat. I did a routine consisting of push-ups, split squat jumps, jump squats (as high as you can) and combinations of these. For example, do a jump squat then drop into a push up and come back up into another jump squat, etc. Once you break a sweat and feel winded, slow down and stretch again.
2) Do light stretches throughout the day, before your event starts. When you feel low on energy or not focused do 10 pushups or 10 split squat jumps. The goal is to do just enough to get the blood flowing again, but don't break a sweat.
3) About 20 minutes before doing starting a big cube BLD event do light, but slightly more rigorous, workout than step 2. Do 20 pushups, 20 split squat jumps, and 10 jump squats. As you start to break a light sweat slow it down and stretch again. After stretching review images/do whatever you usually do shortly before the event.
4) Solve.
5) In between solves try to get some time to get a short break. If this is not possible due to the competition time constraints then obviously skip this step and just stretch again instead. During the short break between solves do maybe 10 split squat jumps and 5-10 pushups. Just enough to get the blood flowing again.
6) Do remaining solves in the round repeating steps 4 and 5.
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Anyway that is what I did and I really think it helped. I felt great all day because I felt like I was being physical and was breaking a light sweat a couple times during the day. Not enough to be over exerted like I did at Horizons, but enough to be useful.
I will certainly make exercise a mandatory part of my warm-up whenever doing a big cube BLD event. It might just be placebo effect, but I've heard this mentioned from the memory sports people, and now that I've tried it I feel better when I do it. I think exercise can play a not insignificant role in improving your accuracy/times/feeling for big cube BLD events.
Hope this helps someone,
Chris