Fatigue from other training and its effects upon velocity scores
One of the best uses of velocity scores, apart from monitoring progress, is to understand the link between fatigue, strength and velocity scores. For each individual, strength and velocity scores are strongly related, in so far as, certain changes in velocity when lifting certain resistances may mean a change in strength. My advice is don't bother with mean/average velocity changes less than 0.04 or 0.05 m/s. The reasons for this are: 1. There is a normal variation in strength or jumping height every day or even between sets on the same day. This amount can be around 2-3 %. That % variation equates to 0.04 to 0.05 m/s on most strength exercises. Another reason is that from a study conducted at the Queensland Academy of Sport and to be published in the Journal of Australian Strength & Conditioning (JASC), the Smallest Worthwhile Change (SWC) in velocity scores for squatting was 0.03 to 0.04 m/s. This SWC is a statistical measure that looks at what is, basically a "worthwhile" change for an athlete. So a change of 0.02 m/s is not strong enough a change to be considered worthwhile or large enough to be meaningful to the athlete. So in my opinion, 0.05 m/s is the minimum to even consider action or be definite about a change in strength. And even then it means about 2.5%1RM. Experienced lifters often feel or report changes of more than this throughout a training week, due to cumulative fatigue. So if you get a change of 0.04 to 0.05 m/s, do you actually need to alter training much or at all? Some coaches carry on as if these small changes will lead to some training catastrophe! So if you get a change of say 0.04 to 0.05 m/s, if have to decide A. is it meaningful ? B. what caused it? C. do i need to alter training content in either the immediate term or in the future? Sometimes, or even often, changes of this amount are just short-term and due to any number of things, but they can be accounted for due to a slight increase in work-load or some factors that decreased recovery (sleep, diet, hydration). Do you really need to drastically alter training or call a meeting of the HIGH PERFORMANCE STAFF because an athletes squat velocity scores are 0.05 m/s lower this week, compared to last?
So I want to detail some data from my Pull-up (chin-up) training from the last month that looks at velocity scores and the effects of being relatively fresh, being fatigued from other activities like four consecutive days of paddling for my surfing or being fatigued from four consecutive days of lifting. And then being fresh again (back to normal training).
Below in Figure 1, you can see a normal training situation for my pull-ups, with the average first-rep velocity of the eight sets being 0.42 m/s. But the next week, in Figure 2, you will see the exact same dosage of sets/reps/rest and the he average first-rep velocity of the eight sets being 0.37 m/s. The change in velocity of 0.05 m/s equates to a decrease in strength of about 2.5 %1RM and was evident from the first set. So what do I do? Do I panic and try to reduce the resistance 2.5% (just how would I do that when I am doing BWT?), do i persist and see if it improves or do I say, "I must be fatigued, therefore I stop doing this exercise"? Well obviously, I just did all my sets as per usual because I knew what my scores were decreased by 0.05 m/s!
I had surfed four days in a row, averaging about 3.2 km a day of paddling (See Figure 3) and had just got out of the surf about 90-minutes before this training session. So the fatigue that accumulates from paddling, using the same musculature as pull-ups (pull-up 1RM strength/BWT and surf paddling speed and endurance are extremely highly correlated, r = >0.90) had temporarily suppressed my strength. No need to panic and alter things. Resumption of normal workloads will result in normal velocity scores and strength levels. Being rainy season where I am, on-shore winds and not much surf are more common at this time of the year, so I knew that this four days of surf would not come about again for a week or more.
But the following week, my training plan called for the same set/rep/rest combos but with the addition of 5kg attached to my body-weight. Do I panic and think "No, I can't because I am down in strength" or plough on, knowing that last weeks decrease in velocity and strength were just temporary fatigue related blips on the training radar? I plough on. In Figure 4, you will see that the velocities with +5 kg were the same as with bodyweight, two-weeks earlier.
But due to social reasons, I had alter my training schedule and to perform four days in a row before the next pull-up session. So again I have a temporary fatigue, due to the accumulation of fatigue and under-recovering. No big deal and to be expected, with the result being a reduction in velocities for the eight sets with +5kg, as is seen in Figure 5. When I am fresher again, they will return to their normal levels. Simple as that.
So it is pretty clear that my pull-up velocities and strength are sensitive to extra workload or to under-recovering, which ever way you want to say it. The typical change for me is about 0.05m/s decrease, equivalent to 2.5% 1RM, between normal training scores and a slightly fatigued training training state. When I am fresher or tapered a little, I will show those scores...but expect a slight bump in velocity lifting the same resistances. That is the nature of PERIODISATION!
So if you understand your training cycle, how you respond to workloads and tapering, velocity scores will provide an even more objective insight and help you plan future training even better. Don't get caught up into the "We must be fresh every session and I need to alter training content if velocity scores drop by 0.01 ms!" hysteria.
But to improve your training, get yourself a Push arm band from my website (click the link below) and start monitoring your velocity scores on your Key Performance Indicator exercises.