Absolute strength is developed with slow velocity between 1.5 m/s - 0.35 m/s, while training maximum velocity the resistance must be low enough to achieve a velocity greater than  1.5m/s. How do you measure the bar velocity accurately?  You could use linear regression equations to predict the bar velocity based on the percentage of the 1RM or you could tell your athlete to move the bar as fast as possible or you could measure it accurately with implementing linear position transducers (LPTs) . 

Novelty gadgets and fads are constantly hitting the market and used by personal trainers to mislead their clients into thinking they are training more effectively.  

However, Exercise rehabilitation professionals and strength coaches have benefited from this technology just because it exists isn’t always justified; it can involve countless hours of training and data mining, including the many headaches and frustrations when it doesn’t work properly or breaks down. In order for me to implement new technology is must allow me to do at least one, if not all, of the following:

1. Something I was unable to do before;

2. Coach more effective;

3. Become a more efficient coach;

4. Provide value added to the athlete;

5. Provide a return on investment (time and money).

Linear Position Transducers

The introduction of linear position transducers (LPTs) into the weight room opened the door to a new world of velocity-based training (VBT). Exercise is typically monitored using volume and intensity, with the latter being measured using a percentage of the maximum weight lifted for one repetition (%1RM). In the pursuit of increasing human physical performance, strength is only part of the equation. How fast someone moves (velocity) and how much work they can do per unit time (power) are critical factors that can dictate who the better performer is. For athletes, this translates into wins and losses. For athletic occupations such as military, police, and firefighters, wins and losses can equate to life and death or safety versus injury.

While most strength coaches have known the value of adding a speed component to training for some time, it had typically been done without much guidance. Confidence had to be given to the verbal cue “move the load as fast as you can” for a prescribed number of repetitions. Adding in the use of a textbook load anywhere from 30-65% of 1RM (westside Barbell using a combined between 30 to 40 percent. The bar speed must be above 1 m/s with Yuri Verkhoshansky stating The bar speed must exceed 1.2 m/s. using 40 percent for most of his explosive strength training, but on occasions, up to 60 percent.

With the implementation of LPTs came the ability to measure velocity and power during a strength training session without the need for advanced motion analysis techniques.

Weight Room Velocity and Power

The most common use of this technology is through an entry/exit testing battery. That is typically done between training phases or at designated times throughout the macrocycle. Using key indicator lifts with a speed component (e.g., jump squat or explosive bench press), velocity and power can be measured to assess the results of the preceding training block or intervention. Incremental loads can be used (e.g., 10%, 25%, 50%, 75%, of bodyweight or 1RM), and an individual velocity or power profile can be created. By using the load at which maximum power is generated, or the maximum velocity achieved for a given load, one is now able to periodise and prescribe using percentages of these values in a similar way to the classic measure of intensity (%1RM).

Intervention

Another use for this technology in the weight room is to ensure the target quality of choice is being trained. Once a maximum power or velocity value is determined, a threshold value can be set. Usually, this is set around 80-90% of the maximum achieved. When consecutive repetitions drop below this number the set or exercise is considered finished, as it would indicate, the athlete is no longer training in a range close to the desired quality. Instead of prescribing an arbitrary amount of repetitions, the individual athlete’s current performance state is dictating how many repetitions are performed. In one workout it might be five repetitions, and in the next workout with the same load it might be ten repetitions. Known as autoregulation, it allows for intra- and inter-individual variation within a session, microcycle or mesocycle. For highly technical movements such as Olympic lifts, this could provide insight into fatigue and quality of work. This is particularly useful because PUSH can detect a drop in velocity drop before the coach can detect a breakdown in technique. This data can help coaches make more informed decisions. In this case I might choose to increase the rest time, lower the load, or proceed to the next exercise.

Using LPTs to deliver VBT checked-off points 1, 2 and 4 on my list above, so adopting their use was a no-brainer for me. However, significant limitations still permeated with points 3 and 5. I still had to create and manage a database in a spreadsheet, manually inputting numbers and investing time into data analysis and presentation. While I have time allocated for this, not all strength coaches do, especially those operating in a fee-for-service model. On top of that, the largest barrier preventing mainstream usage was the price as most LPTs cost thousands of dollars for a single unit. That limited their use to resource-heavy organisations such as professional sport teams, collegiate institutions, and national training centers. It was hard for the everyday exercise professionals to justify the purchase of such equipment as the return on investment from time and cost standpoint clearly wasn’t there.

Wearable Technology

Enter PUSH, a new wearable technology consisting of an accelerometer and gyroscope packed into a small armband. While this technology has been around and used in the weight room before, PUSH is the first device I have come across that address all five of my above-listed requirements. The biggest draw to PUSH in my opinion is the price point. At less than $200 per unit, any athlete or coach can be outfitted with a device for the price of a good pair of training shoes. The cost to outfit the entire team is less than one LPT. Cost is no longer the barrier preventing widespread adoption of this technology, creating a return on investment through points 1-4.

Weight Room Data Management

Addressing point 3, PUSH’s front end interface and data management is easy to use and efficient. It is clear they have invested considerable resources into the software. The back end is doing quite a bit of work under the hood, while the interface feels clean, simple and user-friendly. For me, this was the breaking point on previous accelerometer based devices that have been on the market. They were either too cumbersome from a software standpoint or too limited in what they could do from a hardware standpoint. As a strength coach who feels like he lives in Microsoft excel, I am always searching for a software solution to programming and monitoring. PUSH’s portal and software are potentially the solutions I have been looking to collect weight room data.

Extensible Library

No technology is without its limitations. Right now, the limitation with PUSH is the volume of exercises in their library. However they have created a unique solution around this by adding a manual mode where you can track an exercise that isn’t in the library. Their engineers work their magic and can add it to the library if there is enough demand for it. That means the library will continue to grow as the users generate interest. A library of current supported exercises is available here.

Team Workflow

The part I like most about PUSH is that the hardware is attached to the athlete and not the equipment. That enhances the workflow and ease of use; it is set and go for the entire session. It doesn’t require adjusting the hardware setup for each exercise. For those in more of a personal training setting and working with clients one-on-one, a single unit would suffice as you could switch profiles in between sessions and track your metrics for the entire day. For team settings, their price point allows each athlete to have their own band, allowing me to collect metrics more efficiently without the need for swapping units or changing profiles mid-session. The reporting side is very user-friendly, and the graphics are easily understood by athletes and coaches alike.

Regardless of a strength coach’s level of engagement with the current state of technology, velocity based training is a must for anyone trying to increase human athletic performance. Having a tool such as PUSH can increase the effectiveness and add value to this method of training. Now that this technology has become accessible and affordable, I suggest that any exercise professional looking enhance their programming and monitoring consider adding it to their toolbox.

By Christopher Glaeser | November 26, 2014

https://www.freelapusa.com/velocity-based-training-in-the-weight-room-why-i-push/