Biometric Tendo Unit Training

One of the unique advantages that a Tendo unit provides is that it gives athletes feedback on bar speed or velocity of power output so that they realize how hard they can train. The unique thing about a Tendo is that it will give feedback such that the athlete knows how hard he/she is training , or if they can push themselves harder. It will also give them a facilitated motor pattern. I truly believe that by seeing that feedback number and pushing themselves, athletes learn how to apply force into the ground. The Tendo unit is such a unique tool for this. Please be aware that the technique could get out of control based upon the amount of effort the athletes are pushing into the bar and the floor. So please be aware and don’t let technique get out of control when using these methods.

How did you come across the drop-off methods for your biometric training?

Much of my biometric method and the amount of the percentage drop-off that is used came from the necessity of training large large groups of athletes with varying abilities. For example, I have fifth year seniors with high work capacities who can train through the roof, and first year freshman who have never trained before. This was a realization that I dealt with as a college strength coach. I needed to be able to control and regulate the sets, reps, and volumes to provide optimal training for my athletes. In talking with great track coaches like Phil Lundin and college strength coaches like Todd Hamer, it’s obvious that in this type of training the quality and speed must remain high. This has been confirmed by many conversations with sport biomechanist Dr. Michael Yessis.

Quality and speed are king in sports. This has always been my guideline for training at least 90 percent of the time. We all know that you have to build work capacity in the human so that you can have greater speed quality development at a later date, but the guidelines should be for speed. That’s how the biometric methods came to be. I, or any other strength coach, didn’t develop this specifically. You see it in many training methodologies throughout history such as in track and field and swimming programs. One of the track coaches I talked to asked me a question: “How many sets and reps should I do to make sure that I get optimal training without overtraining? How do I know how to do the correct amount?”

The answer—you take a percentage drop-off. For example, if an athlete’s best effort on any particular distance is four seconds, have the athlete continue to run that particular distance until 4.12 seconds or slower. That would be the slowest point and the training point at which you would stop the athlete. In this scenario, we’re using time as the plyometric measure for the

amount of training that can be completed. The other possibility is if you’re doing another three percent drop-off in high quality work. You could take a flying thirty meters and reduce it by one meter. So you would take the best thirty meter effort the athlete has. If it was two seconds, you would reduce the distance the athlete runs and have him continue to do 29-meter flying runs until he ran two seconds or slower. You can always manipulate the rest, but in most cases, you would want the rest to be maximal because you’re training for maximal effort, which is something we can get into later. The concept from various coaches developed into my time set controls biometric training. Essentially, you’re doing the same thing as the track coach did to regulate training, but you would do it in the weight room. You can take a set weight with an exercise, and if you do five reps in four seconds, you will keep doing five repetitions until you do the same weight in 4.12 seconds. At that point, your regulation of sets becomes dictated by time.

I found this method to be optimal with submaximal days. For example, in the undulated periodization model, you would complete this on day one using the three training methods. There are other ways to manipulate the time sets, but I have found this to be optimal for measuring the time it would take an experienced coach with a stopwatch in timing the sets. Please keep in mind that technique is also a variable. If the athlete’s technique changes over the sets, stop the amount of sets you’re doing because the change in technique often increases the time. The athlete won’t have consistent metrics and you won’t be able to continue measuring what he’s doing effectively and correctly. As with everything in maximal effort training—even with the submaximal loads— you would most likely focus on technique.

How did you come up with various drop-off percentages?

The drop-off percentages that I use in my programming with more advanced athletes basically came from simple concepts from testing an athlete in the vertical at the beginning of a workout. Train the athlete for that particular day. Stop when the vertical goes back up and the athlete isn’t fatigued and still supercompensating with the jump squat height. In the beginning, I used some

other device for measuring the percentage of the drop-offs that the athlete performed and how soon they recovered. Then I used those methods to provide myself with the frequency (how often) the athlete should train again. For example, I had a professional athlete who had camp in four weeks. He hadn’t worked upper body all summer and had come to me for help. He was a fighter in the NHL and informed me that he must get his bench to over ten reps with 225 pounds. On day one, we tested him, and he could only do two reps. He had been to a higher level prior to that, but at this point in time and over the summer, he had never trained upper body. As a result, we went with a 1–2 percent drop off and benched every day for four weeks. By the end of his training with me at four and a half weeks, we rep tested him and he went to thirteen reps with 225 pounds. Understand that this athlete had been close to that level before but needed to train the motor skill to get better and do it as often as he could. Some days we only got six to eight reps in a certain weight. On other days, we did as many as sixteen singles at a certain percentage above or below 225 pounds. Again, we could keep training every day because we regulated the amount of drop-off and the quality of the drop-off that he performed each day, so he didn’t overtrain and was able to heal for 24 hours.


One of the most amazing results I’ve seen from a plyometric method was an elite, professional athlete with large work capacity potential perform his training sets for roughly four sets of squats at a body weight of 205 pounds. He was using 295 pounds and would do one repetition, rest 15 seconds, and do another repetition. With our drop-off percentage guidelines, he achieved 3–4 percent. He was able in one set to perform 31 repetitions and not drop-off more than three percent of his bar speed during that set. That particular day, the athlete did over seventy repetitions of the back squat at 295 pounds at a very high velocity. Essentially, some could say it was a jump squat because he was coming off the ground at the top due to acceleration. He was accelerating all the way through the bar. If he had done eighty repetitions, we would have overtrained him. If he had done fifty repetitions, he would have been undertrained for that particular workout and the demands we imposed on him.

How do you use biometric training on max effort days?

One of the great things about the max effort training is that it gives the athletes a huge amount of feedback in their ability to push against a lot of force. In my undulated weekly model, it would go on the max effort day, which would be day two loading methods. I often use Tendo training for maximal velocity training in regards to regulating max effort days. Essentially, what you’re doing with the Tendo is measuring the bar speed. This will give you an understanding of how many sets an athlete should do on a particular day. I often only do singles or clusters with this particular method, so please be aware that anything more than a single with maximal loads probably isn’t optimal. For example, I had an athlete regulate in regards to a three percent drop off.

This particular professional athlete weighed 205 pounds and back squatted 295 pounds for 72 singles over four sets on one day. He came in two days later. We tested him and he was able to repeat things that he did two days prior during the workout in regards to bar speed and vertical jump height. We know this athlete’s work capacity ability at this point and training age. He was able to handle a 2–3 percent drop-off on training in every other day frequency. In one of the sets, this particular athlete did 32 reps in a row before he reached a three percent drop-off. The max effort biometric training is inspired by the Bulgarians. They hit maximal effort on a particular day to find out where the athlete was and then reduced the weight by five to ten kilos and hit singles until either technique failed or the weight couldn’t be lifted any more in that particular workout. This isn’t confirmed through Bulgarian coaches—only through people who have talked to many Bulgarian coaches over the years. It seems to be a very effective method for training maximal effort. The biggest key for maximal effort is being able to find the drop-off point on a percentage base in regards to how much the athlete should reduce bar speed and when the next time his training will take place.

By: Cal Dietz


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