Every once in a while we come across an idea that instantly resonates with us. We instantly understand that this idea is a solution to a real problem. Maybe not only the solution to one, but even the solution to a variety of problems. Often, this idea is so simple that the first reaction is : „Well, obviously! Why didnt anybody think of that before?“, or „Why did we do it any differently until now?”
One of these ideas for me is „Light Variable Resistance Training“. I came across this idea in the winter of 2017 at a seminar hosted by Henk Kreijenhof in the Netherlands. It was a small and intimate „invite-only“ seminar with top coaches and scientists.
It was Joe Dolcetti, a Canadian-born strength&conditioning coach / inventor / entrepreneur, who introduced us to the „EXOGEN“ suit. It is a full body tight-fit suit on which light weights of 50-300g can be attached anywhere on the body. He only gave a short presentation, which focussed mainly on the results athletes had with the suit. He showed videos of MLB pitchers, NHL players, UFC Fighters, (Inter)National Champions in Hockey, Bow Shooting, MotoGP and Swimming using the suit.
After overcoming the initial „What will only a few grams do?“ objection, everybody in the room instantly understood why this is such a valuable tool. It is a combined solution to many different challenges I have been facing.
Challenge #1 : How do I improve sport-specific speed and power without keeping players away from the game too long?
We cannot only play the game. If we only play the game we will always be held back by our same inadequacies. We have to isolate our weakest link, be it a certain energy system, strength quality or motor pattern. Thats the whole conceptual foundation of preparatory training. Building general strength, endurance and motor patterns, also called General Physical Preparation (GPP) is very valuable when we are far away from peaking. So especially young / intermediate athletes or elite athletes in their off-season certainly benefit from general gym or track workouts. In some sports like American Football, Rugby, Icehockey or Track Cycling a minimum level of strength is necessary to be part of the worlds elite. But where do we reach the point of diminishing returns? I think the athletes often times know a lot better than the strength&conditioning coaches where that point is. I can recount many many instances where high level athletes asked me if it was really necessary to strength train (squatting, deadlifting, olympic lifts). They felt it had nothing to do with their sport. And of course I had the usual response about specificity, transference, injury prevention and strength/power reserve, but still I always felt they had a valid point! Becoming stronger will improve on-field performance (in weak athletes). But at the highest level, usually the athletes are not too weak. They have the necessary foundation. What they really need now is a lot more specific work. ON THE FIELD.
I would have loved to have the ability to strength/power train them ON THE FIELD!
You know, for energy systems training that is fairly easy. We have always done most of the energy systems work in pro basketball or icehockey on the court or on the ice. By manipulating field size, work/rest ratios, group size and drill requirements it is easy to target what you are after, while the kids just play their game. Everybody is happy. But what about strength training? When it comes to strength training we always leave the field, we leave the beloved game, and go to the gym. Yeah we can try to integrate it as close as possible. Lets have some sets of strength training, and then do some shooting drills. We have done that of course. In basketball it is fairly easy when the infrastructure is right, but in icehockey thats just not possible.
I think Light Variable Resistance Training (LVRT) is the strength/power/speed equivalent of small sided games. What small sided games are for energy systems work, LVRT is for strength/power work. It keeps the kids in the game, and still isolates and challenges the physiological weak link.
I think Light Variable Resistance Training (LVRT) is the strength/power equivalent of small sided games. What small sided games are for energy systems work, LVRT is for strength/power work. Click To Tweet
Challenge #2 : How do I optimize motor learning without talking?
I know that when I talk a lot during the session, then it was a terrible learning experience for the athlete. Me talking is a fairly good sign that I did not find a good way to have them experience movement. There is a huge difference between thinking/understanding and feeling/experiencing. HUUUGE difference!
Especially when it comes to athletic development and motor learning I always strive for the experience of movement, instead of the understanding of movement. When we THINK about movement, we will be slow. We will be inefficient, we will be robotic. The only way to be efficient and in flow is to NOT think about movement. Many coaches believe that we first have to think about/understand the movement, and then learn to apply without thinking. I think that is stupid and it is not how this works. I dont think we have to take the long de-tour through our frontal cortex to learn movement. I believe in bypassing the frontal cortex entirely.
When we THINK about movement, we will be slow. We will be inefficient, we will be robotic. The only way to be efficient and in flow is to FEEL movement. Click To Tweet
For us as coaches it is incredibly difficult to teach without talking. It requires from us to shape the environment for specific learning. For example when we want to teach a high release point to a thrower we can talk about the high release point, or we can just stand right next to him. When we stand right next to him the only possible solution to throw the ball without touching us is to have a high release point. I believe the second method is far quicker and will stick a lot better than the first option.
Shaping the environment for learning becomes harder and harder the closer we get to the actual speed and kaos of the game.
How do we teach this high release point in the actual game? LVRT might be just the solution to that. By specifically placing the weight on points of the body that trigger that high release point, releasing the ball high will FEEL much smoother to the athlete than a low release point. With LVRT we can take the constraints-led approach to motor learning into the speed and kaos of the game.
Challenge #3 : How do I fine-tune motor patterns at high velocities?
This is similar to challenge #2, but here I specifically refer to low vs high velocity motor patterns. This becomes relevant in late phase return to game situations. We know the importance of movement timing and joint angles when it comes to reducing the risk of (re)injury. These are fairly easy to teach and improve upon in a controlled environment. The physical therapist will spend the majority of his time improving this movement efficiency in early phase rehab and return to game. He might use neuromuscular techniques like reactive neuromuscular training (RNT) to improve the muscular timing/activity of the hip muscles in controlling the knee while squatting, while landing or while jumping. RNT is based on the principle that by pulling a limb into a „faulty“ position, the body will auto-correct by activating the more efficient pattern. So we use these principles in low-speed, high-control environments. But what happens during late-phase return to game stages, when the athlete is back on the field doing high-speed movements in a low-control environment? We look at slow-motion video and we see the „faulty“ patterns re-emerge. While the body was able to control the efficient pattern in a low-speed environment, in a high-speed environment the control-threshold seems to have been crossed and it all breaks down again. We see this over and over again, and pushing the threshold of control to higher and higher levels of speed/force, is the holy grail of effective return to game strategies.
I think LVRT can serve as a neuromuscular trigger to teach efficient movement in high speed environments. It is not so much teaching as it is automatic, experiential, in-flight adjustment of movement.
LVRT can serve as a neuromuscular trigger to teach efficient movement in high speed environments. Click To Tweet
So how can something that looks like a weight-vest from the outside, solve all these challenges?
Light can be Heavy
When we think of improving power and speed, we instantly think of overloading movement. But how much of an overload is really needed to improve power/speed? When Joe Dolcetti asked this question my S&C monkey mind instantly thought of the things I was trained to think of. %RM for power development, SPP, Force-Velocity relationships, about transference, biodynamic correspondence and all that jazz. Let us not fall in that trap. That’s a thought pattern of strength/power training in the gym. We might instantly think about some form of gym training. Maybe olympic lifts, maybe squatting, or maybe something more specific on a KEISER cable pulley. Or maybe we are thinking about specific physical preparation (SPP) as put forward by Verkoshansky and recently re-furbished by Frans Bosch. That is our boxed strength&conditioning mind. Let us not do that. Lets remember that the goal of strength&conditioning is NOT to make somebody stronger or more powerful in our controlled environment. The goal is to make him win more competitions. Thats it. So lets start our thought process at the game. At the movements of the game.
Let us remember that the goal of strength&conditioning is NOT to make somebody stronger or more powerful in our controlled environment. The goal is to make him win more competitions. Click To Tweet
So again, how much overload is really needed to push his movement on the next level? It might only be a few grams really. At the speed at which sport happens, a few grams produce A LOT of force. A golf ball only weighs a few grams. I do not want to get hit by that. So when combined with SPEED a light weight can produce heavy forces. Many pro athletes who have worked with LVRT will tell you instantly that 200g is HEAVY when it is placed in the right spot at the high speeds of actual competition.
Lee Chong Wei, current world #2 in badminton, uses small weights with the EXOGEN suit when he is doing a high-speed ball shuttle drill. He self-selected a weight of only 600g for this drill. He uses the vest for the first 30 minutes of his practice and then takes it off to elicit a post-activation potentiation (PAP) effect. Traditionally weight vests of 5-10kg are being used in badminton. Lee Chong Wei likes the small weight, strategically placed around the center of mass, a lot better, because his mechanics are still sound and he moves at high speeds.
In this video Professional Baseball Pitcher Kyle Lotzkar only uses 200-500g on his upper arm. He likes to place the loads close to the shoulder, because weight being placed more distally, would be too much of an overload. That is also why he dislikes weighted baseballs:
'Weighted balls feel terrible on my shoulder. The traction and feeling with the light loads placed over my arm and shoulder feels so much better. My arm has never felt this good before Click To Tweet
Inertia is a great teacher
When we teach movement in a controlled environment we use light resistance via touch or pulling with a band. A golf teacher might stand behind his athlete to guide the movement. That is gentle pushing and pulling to create an „AHA“ effect in the athletes nervous system. Also, we all know the famous mini band drills to teach knee position. So what does that drill do? The bands pull the knee to the inside, which leads to an automatic response from the athletes nervous system to drive the knee out from the hips and feet. Now, and this is hard to grasp for many people, but I do my best to explain that, inertia in high-speeds can have the same teaching effect.
Imagine I place a 50g weight on the inside of your knee. Then I tell you to sprint. What happens with that weight and your leg when you sprint? When you drive your leg forward, your muscles will have to overcome the laziness (inertia) of those 50g. And because they are placed on the inside of your leg, your leg will experience an internal rotatory force. To counter that your external rotators will have to activate to keep the leg in a straight position. You understand how inertia makes low weights at high speeds a great teacher for movement?
Lets take another example from swimming. In swimming it is important to keep your recovery arm (the one outside of the water) in internal rotation. This is important for body position in the water and a good re-entry into the water. When an athlete has trouble keeping his arm in internal rotation we can take him out of the water, show him video, explain the mistake, and give other coaching advice, or we can just attach a 100g weight to his tricep area. This 100g weight will pull him into external rotation, and the athlete will automatically counter with more internal rotation.
Early indications from cutting edge pilot research coming out of the pool at AUT-SPRINZ indicates very exciting and likely significant PAP changes on swim performances with Elite level swimmers over 200m . A single, acute PAP warm-up with only 300-500 grams specifically loaded on the upper arm may be able to improve 200m (split) times by as much as 1-2 seconds – that’s the difference between a gold medal and not even qualifying at the world level. Who would have thought resistance training had a place directly in the pool and not just dryland, especially this light. Of course at this early stage there is still further research and analysis needed on the data but the early indications are there is some potential quantum leaps with this technology on the horizon.
A single, acute PAP warm-up with only 300-500 grams specifically loaded on the upper arm may be able to improve 200m (split) times by as much as 1-2 seconds - that's the difference between a gold medal and not even qualifying at the… Click To Tweet
Inertia works in both directions. Overcoming inertia can teach the body to COUNTER the inertia. Breaking inertia can pull the body into new ranges of motion for an „ahhh thats how it should feel“ effect. In distance running this is applied for fixing stride issues. A small load placed at the back of the lower leg can increase stride length to show the athlete what a long stride feels like. Placing the load at the front of the leg will decrease stride length initially. A load is placed there for long term resistance training to improve stride length in the long run.
Most Coaches who work with LVRT will use inertia initially to pull the athlete into the right technique -> REALIZATION, and then place the load in a way that the load pulls them into the mistake to force long-term ADAPTATION.
Most Coaches who work with LVRT will use inertia initially to pull the athlete into the right technique -> REALIZATION, and then place the load in a way that the load pulls them into the mistake to force long-term ADAPTATION. Click To Tweet
Movement is Rotational
Rightfully so you might ask yourself : „What will a couple hundred grams do to my performance, when my sports equipment weighs a lot more than that already“.
The key is systemic vs. Localised loading. The weight of protective equipment, of shirts, shorts, or even shoes is evenly distributed, especially when it comes to balancing rotational torques. Usually the inside of a shoe is not heavier than the outside or vice-versa.
With the EXOGEN suit it is possible to create very specific and intentional torque asymmetries to drive motor learning. These asymmetries might be used to balance out intrinsic asymmetries of the athlete in the same manner as 5g inside the rim of cars is being used to balance the trim of the tyres. So if an athlete has an intrinsic motor asymmetry that leads to non-optimal sporting outcomes, then small weights placed in the right spots can balance the athlete out.
Asymmetries can also be used for learning effect in terms of pulling the athlete in the right motor pattern as I illustrated earlier in the example of stride lengths in long distance running.
The asymmetry can also be used as a rotational resistance to work against, like a small load placed on the inside of the thigh/knee to invite external rotation at the hip.
So the key is really the asymmetrical loading. Not in terms of left/right asymmetry, but in terms of asymmetrical rotational torque.
Of course it is possible to place more weight on the left leg, than the right leg in sprinting. But we shouldn’t think of it linearly as „more resistance for the left leg“, but rather we need to think of that situation as asymmetrical rotational torque that our whole system has to balance out.
Some placements of weights will worsen our performance, and some weight placements improve our performance. Like most things in high performance it is about try&error. Place the weight, sprint/throw/slam/jump, evaluate the outcome, and then re-position the weight until outcome, or „feel“, is optimal.
But that’s also another aspect I like about this tool/idea. It puts ownership in the athletes hands. The athlete & technical coach are the ones who make the decisions about the weight and the placement of the weight. And it is all about the outcome on the field.
Using Post-Activation Potentiation
When I played American Football in College I used to wear heavier shoes during practice week and lighter shoes during the games. Baseball players warm up with weighted bats or balls. We already use light weights for post-activation potentiation in some sports. But I have never thought about using PAP with my athletes in a way, where we slightly load the first half of practice, then take the weights off and continue unloaded. I have done that with weight vests, but that is different. Light weights, placed in asymmetrical positions to create asymmetrical torque, and then remove them later.
Joe Dolcetti shared the story of him being invited by the MotoGP team of Malaysia when he let Zulfahmi Khairuddin try out the EXOGEN suit. He placed 300g on each upper arm. Then Zulfahmi put on his leather suit, which weighed over 5kg. Joe thought to himself : „Damn, this is never going to work. What are 600g to 5kg?“.
But after riding the motorbike for 10 minutes with the extra 600g on the upper arms, Zulfahmi said that it was 40% (!) harder than without the 600g. When he took off the 600g and rode again, he instantly broke the local track record. The loads were specifically placed to drive his arms down and into internal rotation, for him to work into external rotation.
Here is the video :
I think LVRT really fills a gap here. The gap between the actual sport and preparatory training. The gap between skill acquisition and neuromuscular development. I instantly fall in love with ideas or concepts that bridge gaps and thereby improve communication. I see LVRT as a great catalyst for communication between technical coaches and physiological coaches. I am really looking forward to learning how other coaches and athletes apply LVRT in training/competition. I think there is still a lot to learn regarding optimal loading, loading placement, periodisation, and quantification/monitoring. Currently, a lot of scientific studies are running to evaluate the effects of LVRT. I think we are at least 15 years away from understanding the effects of LVRT on motor learning. That is why I will be far more interested in your experiences with LVRT as coaches and athletes in the near future. Exciting times. Post in the comments your experiences with LVRT or similar!
We are at least 15 years away from understanding the effects of LVRT on motor learning. Click To Tweet
I recently visited Joe Dolcetti in Malaysia and we recorded an in-depth podcast on LVRT. You can check it out HERE.
May the FLOW be with you!
Gerrit Keferstein is a Medical Doctor specialised in Performance & Functional Medicine. He is most known for his work on the optimisation of recovery and adaptation in elite athletes.