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On the current training block, which has a strength focus, I’ve programmed what are most commonly referred to as max effort days. These are strength development days on which you work up to the heaviest load you can manage for a particular amount of reps. On the published program this will usually be read as “build to your heaviest 5 for the day” or “5RM.” The movements programmed will stay the same for several weeks but the reps vary, and the reps typically decrease weekly in favour of more load.

During a training block, as opposed to during testing, these max effort days are programmed to develop strength and not to test strength. While it may be an all-time record, it’s not what we’re expecting. It’s simply the most you are capable of on that day for that lift. In order to get stronger you have to train heavy – as close as possible to your maximum abilities – often. So in order to gain the benefits of a max effort day, you have to max out.

There’s a lot of science behind the method, but let’s keep it simple. The nervous system needs to get better at switching on more muscle fibres at the the correct time to get stronger. By maxing out, we light up the fibres that wouldn’t be turned on when not working to max. The musculoskeletal system needs to get better at moving load. This means connective tissue (ligaments and tendons) need to grow and strengthen, and muscles need to grow. For that to happen you need time under (relatively) high loads. And just as importantly, you need to be mentally prepared to move maximum loads and regular max effort days do just that – it gets you comfortable under the bar.

Remember, strength is just one of the 10 recognised physical traits we aim to develop in CrossFit. It is however core to our program, and probably more so than most other gyms, because it takes so much longer to develop than most of the other physical traits and because strength through good positions develops better positions under fatigue.

So on max effort days, max out. Really work to find the heaviest load, with good positions, for that day. Don’t be bummed, though, if on a max effort day you don’t hit a PB. If you do, celebrate it, but if not, remember that the purpose of the max effort day is to develop strength. We’ll test that during test week, and life will test that when you least expect it!


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