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Archive for the ‘Sport Specific Training’ Category

If you’re an intelligent strength coach, then chances are you can relate to this article. In training athletes over the past several years, I’ve been very surprised by some of the stupid things that coaches do with their athletes. I’m also constantly amazed at things that former strength coaches have done with some of the athletes I’ve trained. Here are ten stupid things that coaches and strength coaches do with their athletes:

1. Exercise as Punishment

Strength coaches and coaches are supposed to have their programs planned ahead of time. There are many effective ways to plan and periodize programs, and a good coach prescribes the optimal amount of volume and intensity to yield the specific training effect. If on any given day a coach decides to punish his or her athletes with copious amounts of push ups, up-downs, stadiums, or jogging, then that coach doesn’t know what in the hell he or she is doing. If the coach has these “punishments” strategically built into the session in advance, then that’s a little bit better than just “winging it,” but here are three reasons why this strategy is detrimental to the athlete: 

  1. You don’t want athletes fearing exercise. You want them to enjoy training. Punishing them in this manner is not helpful.
  2. Second, performing excessive volume on any particular movement pattern can invoke too much fatigue and initiate the overreaching/overtraining process, or lead to stagnation or injury. At the very least it will hamper the workouts planned on the following couple of days.
  3. Endurance work interferes with power (Hakkinen et al. 2002). There’s a fine line between optimal stamina/power endurance/work capacity and maximum power production.

I’ve heard of some coaches who say, “I will break my athletes.” Athletes aren’t horses. I prefer to build my athletes up so they don’t break! Plan out the appropriate amount of stimulus that will spark positive adaptation, and discipline athletes in ways that don’t involve bringing more fatigue to the plate.

2. Twice-a-Day Workouts to Kick-Off the Season

Over the summer or during off-seasons, many athletes get lazy and sit around playing video games. In fact, many athletes don’t train at all during this time. Their coordination degrades, their tissues decrease in strength, and their levels of power, strength, and endurance plummet. As long as you gradually build them back up, athletes will quickly adapt to previous levels of fitness and structural integrity. Think of it as rehabilitation – you gradually increase the stimuli over the course of a month or so and voila! Your athletes are all healthy, strong and fit.

Taking an athlete who hasn’t trained all summer long and starting them off with 2 (I’ve even heard of 3x/days) strenuous workouts per day is absolutely asinine! Doing this for a couple of weeks is a sure-fire way to initiate overreaching, promote soft-tissue injuries, and delay strength and power gains. Some coaches feel that soreness is a prerequisite for results, which is a load of bull. You can certainly have your athletes train two or three times per day, as long as you take a couple of weeks to build up to these levels. Think of Milo of Crotona and gradually progress.

 

I’ve heard coaches say, “I have to shock them into adaptation.” I’ve had very much success with athletes by never “shocking” their bodies too much at one setting, and rarely getting them sore.

When I introduce a new exercise, I’m very conservative and I don’t let them push it too hard. I see how their bodies react and adjust accordingly. This is especially important for exercises known to create a lot of soreness such as heavy lunges, Bulgarian squats, deadlifts, and ab wheel rollouts. My goal is to never get my athletes too sore so that every workout can be productive, and so they never get overly-tight and bound-up.

3. Strength Training in the Early Morning

During sleep, compressive loading on the intervertebral discs is reduced, which allows the discs to absorb more fluid and increase in volume (Urban and McMullin 1988). During the day, this extra water is expelled as normal daily spinal loading and movement ensues. In the early morning, intradiscal pressure is 240% higher than prior to going to bed (Wilke et al. 1999). Furthermore, bending stresses are increased at the discs by 300% and at the ligaments of the neural arch by 80% due to  hydration and absence of creep (Adams et al. 1987).

As the day goes on, discs bulge more, become stiffer in compression, become more flexible in bending, becomes more elastic, have a higher affinity for water, and the likelihood of prolapse becomes more difficult (Adams et al. 1990).

Many strength coaches have their athletes training at 6:00 a.m, doing back squats, deadlifts, and sit ups. This is probably one hour after they athletes have risen from bed. The chances of sudden spinal disc or ligament injury or even subtle disc damage is greatly increased under this hyper-hydrated state. Either train later in the day, or create “low-back friendly routines” to decrease the risk of injury. If you can’t find a way to train at least 2-3 hours after the athletes have awakened, then here are some ways to decrease the likelihood of spinal injury during early-morning training:

  • prolonged warm-ups – spinal muscular contractions cause the majority of compressive loading, and the longer you can prolong heavy lifting while moving around, the more water will be pumped out of the discs so safer levels of hydration are reached
  •  front squats over back squats – although the compressive load is probably similar between the two lifts, as front squats involve higher anterior core contractions while back squats involve heavier loads and higher posterior core contractions, back squats involve greater forward trunk lean and encourage more forward bending which imposes higher shear and bending moments on the spine 
  • speed deadlifts or power cleans over deadlifts – although compressive loading may be similar in these movements due to similar core muscular contractions and higher speeds of execution, deadlifts encourage more forward bending which imposes higher shear and bending moments on the spine 
  • ditch the heavy bilateral lower body lifts – instead opt for Bulgarian split squats, reverse lunges, high step ups, and single leg RDL’s rather than heavy squats and deadlifts – you probably get 75% of the spinal loading due to less erector spinae contraction and lighter external loads
  • ditch the core training, or at least train the core at the end of the workout – compression, torsion, shear, and bending stresses are highly dangerous when the discs are hyper-hydrated, and even a presumably safe core exercise is not safe under these conditions

4. No Concern for Strength

I’ve heard many coaches say, “I don’t care about strength.” How many articles in support of the positive impact of strength in relation to power production need to be published before some of these idiotic coaches realize the importance of strength as it pertains to athletic performance? There is a huge relationship between strength, muscle cross-sectional area (CSA), myosin heavy chain (MHC) isoform composition, and rate of force development (RFD)(Tipton 2006).

If you are a coach and you don’t acknowledge the role of strength in improved athletic performance, then shame on you! Your athletes deserve much better.

5. Over-Focus on Strength

Many coaches are at the opposite end of the spectrum. Strength is all they care about, to the point where they stop doing “athletic things” in training and focus solely on heavy, slow lifts. If all you ever do is slow training your body will adapt by getting better at producing force over a prolonged interval. You want to be able to produce tremendous force over rapid or prolonged intervals, and there’s an optimal way to achieve this.

Strength training works best when trained concurrently along with sprints, plyometrics, ballistics, and agility work. Combined training is superior for the production of power in comparison to resistance training alone (Kostzamanidis et al. 2005).

6. No Auto-Regulation

Auto-regulatory training is vital to maximum performance. Recently it has been shown to be more effective than linear periodization (Mann et al. 2010). It can be used within any type of periodization system, and it simply involves paying attention to biofeedback, listening to what the body is saying, and adjusting accordingly. While I don’t like “cookie-cutter programs,” I am in support of flexible templates.

A good coach can create a great plan on paper, but the best coaches know how to stray from the plan when necessary. If the athlete is overly-sore, back off and train hard the following day. If the athlete didn’t sleep well or has a lot of stress in his or her life, take it easy. If the athlete is feeling great and is all jacked up, smoking the heaviest lift you planned for the day like it was cupcakes, then go heavier and try to set a new PR. Align the stimulus with their physiologic state and watch your athletes adapt more proficiently.

7. No Assessment/Screening/Evaluation

Many coaches have never learned how to assess joint range of motion or fundamental movement patterns. This is very sad, as many times all you have to do is improve flexibility in a particular direction in the hips, spine, ankles, or shoulders and it completely changes an athlete’s form on big lifts and cleans up poor movement patterns when running, jumping, throwing, and/or swinging.

Good form involves proper mobility, stability, and motor control. Any dysfunction in these three areas will reveal itself in movement. The quicker you can pinpoint this dysfunction and eliminate it, the faster your athletes will progress.

There are many ways to assess and screen athletes, but at the very least you should know what normal ranges of motion are in the ankles, hips, spine, shoulders, and neck. You should know what good form looks like in an overhead squat pattern, an active straight leg raise pattern, a push up, static lunge, glute bridge, standing knee raise, db overhead press, and bird dog.

Good coaches evaluate performance measures regularly. They know whether their athletes have gained or lost range of motion, coordination, strength, power, speed, and endurance. Testing can be worked its way into the program without interfering with the schedule. Evaluation is often what separates great coaches from good coaches.

Depending on the sport, you may want to test your athletes’: 

  • breathing patterns
  • posture
  • joint ROM’s
  • fundamental movement patterns
  • core stability endurance from all directions
  • vertical jump
  • broad jump
  • 10-meter sprint
  • 40-yard dash
  • backward medball toss
  • t-test
  • medball shotput
  • max bench
  • max squat
  • max deadlift, and
  • max chin up

One question I often ask trainers and coaches is, “How do you know your athletes are getting better?” Think about it. 

8. No Knowledge of Directional Load Vectors 

In sports we move in predictable directions. We jump, sprint, cut, backpedal, and rotate. These same directions need to be trained in the weightroom. Many times I’ll look at a coach’s program and all I’ll see is heavy sagittal plane lifts involving axial, anteroposterior, and posteroanterior vectors. 

The best coaches know how to get their athletes strong, powerful, and fast in all directions, which requires a good blend of strength, power, and reactive training from the various vectors. Axial, anteroposterior, posteroanterior, mediolateral, lateromedial, and torsional vectors should be trained in order to maximize athletic performance.

 

9. Poor Instincts About Form

There are three types of strength coaches: 

  1. Those who allow way too sloppy of form and expose their athletes to way too much risk at the expense of “going heavier”
  2. Those who are way too conservative and think that every repetition should look like a robot is performing the lift
  3. Those who know the perfect balance

The best strength coaches get their athletes very strong while using good form. I’d guess that 60% of coaches are too sloppy, 20% of coaches are too strict, and 20% have “the eye” for great form while simultaneously producing strong specimens. 

10. No Specialization and Individualization 

Your job as a coach is also to analyze the individual’s strengths and weaknesses in order to bring up their weak link, and to analyze their sport and position in order to create specific exercises and methods according to their needs. 

Routines shouldn’t be the same across the board. Every aspect of the routine should differ from one individual to the next. Each player should have their own warm-up consisting of individualized SMR, stretches, and mobility/activation drills. Each player should have their own power program consisting of sprints, plyos/ballistics, agility drills, and explosive lifts. Each player should have their own strength program consisting of heavy lifts from the various movement patterns and accessory movements for structural balance. 

No two athletes are the same in terms of anatomy, physiology, anthropometry, and psychology. Some players need extra mobility or stability work in a certain joint. Some players distribute stress evenly during lifting and can train heavy more frequently. Some just don’t recover fast and need more time between heavy or explosive bouts. 

Your role as a coach is to ask the athletes questions and learn about their responses to various acute training variables such as exercise selection, frequency, volume, and intensity. In time a good coach will adjust these variables depending on verbal and non-verbal feedback and performance indicators. 

If the coach is training a large volume of athletes and doesn’t have many assistants, then a general system can work well if considerable thought and detail is put into it, but it’s still not optimal. A general system may work best for the given situation, but a program could always be better if more individualization was developed and more assistance was provided from other specialists.    

Conclusion

I hope that coaches learned a thing or two from this article. While I’m proud of all the coaches, strength coaches, and personal trainers out there who care about and believe in their athletes enough to push them hard day in and day out, we should always strive to inject scientific principles into our programming and train in an optimal manner so our athletes achieve the best results possible.

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I was just going through my Youtube videos and I thought it would be a good time to bring some of them back for review.

Here are nine different instructional videos:

Hip Thrust

Squat

Deadlift

Band Hip Rotation

Back Extension

Glute Ham Raise

Box Squat

Rack Pull

Bodyweight Hip Thrust Variations

50 Exercises With JC Bands – Here’s a video of me showing 50 different exercises you can do with the JC Bands. This is a damn good product and probably one of the best portable pieces of equipment for providing a great full body workout. Also, I’m an innovative son-of-a-bitch!

How I Do My EMG Research

Maximum Power Production –

Home Butt Workout – ladies should do this workout several days a week for a healthy butt!

Load Vectors – I filmed this one around 16 months ago! Crazy how time flies.

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Around eight years ago, my friends got together for a slow-pitch softball game. Although I hadn’t swung a bat in years, I managed to crank out five out-of-the-park homeruns that day. One of them cleared the fence by at least a hundred feet. I was pretty surprised…as were my friends. My hitting power sky-rocketed from just getting stronger in the gym. I didn’t do any form of “sport-specific training,” I just got strong at exercises such as squats, deadlifts, walking lunges, back extensions, bench press, weighted dips, military press, chin ups, bent over rows, and one arm rows. Times like these made me realize the importance of strength as it pertains to unleashing your maximal power potential.

Since this time I’ve trained a whole-lotta people, I’ve read a whole-lotta books and articles, and I’ve continued to train hard myself. And I still believe that just getting stronger at basic, compound movements is critical for power. However, power is directional specific, and while strong muscles will get you pretty far, you can get a little bit further if you engage in some specific forms of strength training. I believe that in order to achieve optimal rotary power, one must get strong at big, compound lifts, while also performing rotary strength exercises, rotary power exercises, and practicing specific sports skills.

Below are five excellent rotary exercises that will help maximize your explosive rotational power.

1. The Explosive Rotational Landmine

This is quite different than the normal landmine. Notice the footwork. This allows you to move around the bar and reposition yourself so you can get maximum explosiveness on each rep. Make sure you put the women and children to bed before attempting this exercise – it’s no joke!

2. Overhead Lateral/Rotational Press

This is an amazing core exercise that works the core as a lateral flexor and a rotator.

3. Band Hip Rotations

I’ll keep ranting and raving about this exercise ’til I’m blue in the face. It’s a very difficult exercise to master. You have to set up with your body angled inward a bit toward the line of pull of the band. This way you keep constant tension on the hip rotators as you twist. To reiterate, you don’t line up facing the band, your back foot is further away from the band than the front foot. This exercise activates the glutes like crazy, trains the glutes in their hip external rotation function, and “bridges the gap” between the weightroom and the field. It works the hip internal rotators on the front leg, hip external rotators on the back leg, internal obliques on one side, and external obliques on the other side. It’s the best core exercise that you’re not doing at the moment! If you don’t feel this working the glutes big-time then you’re doing it wrong. Keep working it until you get it right. Monster-mini jump stretch bands work best for this exercise.

4. Low-High Rotary Pull

Here’s an excellent core exercise that works the lower body, core, and upper body pulling musculature in one movement.

5. Low-High Rotary Press

Here’s an excellent core exercise that works the lower body, core, and upper body pressing musculature in one movement.

Hopefully this post has given you some ideas as to how you can go about increasing your rotational power through specific rotary strength training. Spend some time on these and you’ll be belting home runs out of the park like McGwire in no time!

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Bret Contreras: Last year, I created the load vector training model. Of course the system is not perfect, just like all other classification systems. Human movement is quite dynamic and complex, which makes any system of classification very challenging. However, the load vector concept is very intriguing and has merit in the literature.

Chi emailed me his thoughts regarding load vectors last week and I asked him to write a guest blog on the topic since he’s obviously put a lot of thought into it. For those of you who don’t know Chi, he’s a freaky-intelligent guy, a research machine, and an all-around nice guy! And he lives in the Netherlands!

Load Vectors: Less is More!
By Chi Chiu

How do you respond to a blog invite from a highly innovative guy, who turned the explanation of one exercise into a book of 600 pages? How about by writing the shortest guest post ever, about nothing new!

Bret has written extensively about the concept of load vectors (LV) which adds another layer to the use of planes by focusing on the direction of the resistance, instead of the movement. While doing so, he introduces 12 “new” words like anteroposterior, lateromedial, and torsional. Although I enjoyed the concept and love (bio)mechanics, I did not adopt the lingo, because in the weight room we already have less sophisticated, but adequate terminology like push, pull and rotate. If you combine them with the axes (axial, sagittal, and lateral), you basically get most of the LV concept, but on a more intuitive level.

The words push, pull and rotate are generic and tell you something about the forces acting upon the body, while the axes specify the direction. The squat is an axial push exercise and a chin-up an axial pull. The Pallof press however, is a movement in the sagittal plane and looks like a push, hence the press part. In the “new” LV lingo, however, it’s a lateral rotational pull. The LV dictionary for the weight room just got shorter and more intuitive. As a result of it, I’ve seen various people apply those principles on their program design, only minutes after I explained it to them. Just tweak it a little on upper, core, and lower body exercises and you have a general balanced or more specific adapted selection of exercises in no time. By using more intuitive and familiar words, the LV concept gets more accessible and therefore more applicable.

New Terminology

Axial – vertical plane
Sagittal – horizontal plane
Lateral – lateral plane
Push – moving away from the body
Pull – moving toward the body
Rotation – twisting

Examples

Axial Pull – chin up, deadlift, power clean, curl, shrug
Axial Push – military press, squat, lunge, dip
Axial Rotation – landmine, single leg box squat, single leg RDL
Sagittal Pull – inverted row, seated row, back extension
Sagittal Push – push up, bench press, hip thrust, sled push
Sagittal Rotation – bird dog, single leg hip thrust, single arm db bench press, renegade row
Lateral Pull – standing cable adduction
Lateral Push – x-band walk, slideboard lateral slide, lateral raise
Lateral Rotation – Pallof press, cable chop, cable lift

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Over the past few weeks I’ve heard the “Magic 30%” number tossed around on two different occasions in terms of the training load that maximizes power production, so I figured it was time to write an article on this topic. The theory is that we should train athletes with explosive movements at 30% of their 1RM because this is the load that shows the highest peak power outputs and therefore this load will maximize the athletes’ power production and athleticism.

This line of reasoning is faulty for several reasons, but first, let’s look at the research. I’ll state up front that the research is very complicated due to the fact that sometimes “mean power” is used, sometimes “peak power” is used, and sometimes just “power” is used. Different equations and methods are also used in determining max power. Calculations sometimes incorporate bodyweight and sometimes they do not. Different types of movements are employed, for example free weight squat jumps versus machine squat jumps. And finally, different types of subjects are used…various ages, genders, training statuses, types of athletes, levels of strength, etc., which complicates matters as well.

That said, it’s still very valuable to analyze the research. Here are some quick findings on a spectrum of different studies.

Research

Optimal loading for peak power output during the hang power clean in professional rugby players

Peak power output – 80% of 1RM for hang power clean, no significant difference from 40-90%.

Optimal loading for the development of peak power output in professional rugby players

Peak power output at 30% of 1RM for ballistic bench throw and 0% (just bodyweight) for squat jump.

Determining the Optimal Load for Maximal Power Output for the Power Clean and Snatch in Collegiate Male Football Players

Peak power at 80% for Power Clean and Snatch.

The Load That Maximizes the Average Mechanical Power Output During Explosive Bench Press Throws in Highly Trained Athletes

Peak power for Bench throws at 55%.

Optimal loading for peak power output during the hang power clean in professional rugby players.

Peak power for hang power clean at 80%, no significant differences from 40-90%.

The load that maximizes the average mechanical power output during jump squats in power-trained athletes

Peak power for jump squat at 55-59%, no significant differences from 47-63%.

Power outputs of a machine squat-jump across a spectrum of loads

Peak power at 21.6% for jump squat.

Leg power in young women: relationship to body composition, strength, and function

Peak power for leg press at 56-78%.

Human muscle power output during upper- and lower-body exercises

Peak power for Squat at 50-70%, peak power for bench press at 40-60%.

Maximal strength and power characteristics in isometric and dynamic actions of the upper and lower extremities in middle-aged and older men

Peak power at 30-45% for bench press, peak power at 60-70% for half squat.

The relationship between maximal jump-squat power and sprint acceleration in athletes.

Peak power at 30-60% for split jump squat, peak power at 50-70% for squat.

The Effect of Heavy- Vs. Light-Load Jump Squats on the Development of Strength, Power, and Speed

Low load explosive training appears better than high load explosive training for power.

COMPARISON OF OLYMPIC VS. TRADITIONAL POWER LIFTING TRAINING PROGRAMS IN FOOTBALL PLAYERS

Olympic lifting seems better than powerlifting for power.

Velocity specificity, combination training and sport specific tasks.

No difference between strength trained and power trained for netball throw velocity.

Power versus strength-power jump squat training: influence on the load-power relationship.

Combined strength and power training appears better than just power training.

Squat jump training at maximal power loads vs. heavy loads: effect on sprint ability

Power training appears no better than heavy training for sprint speed.

Inter-relationships between machine squat-jump strength, force, power and 10 m sprint times in trained sportsmen

Squat jumps at lighter and heavier loads not well correlated with acceleration.

Conclusions

It appears that each exercise has its own unique range of loading for peak power production, and often the range is pretty broad. The “Magic 30%” figure just doesn’t hold up. Furthermore, individual peak power production can vary considerably from one person to the next, so it’s unwise to generalize and assume that an individual falls in the norm when their anthropometry, physiology, anatomy, etc., could cause them to stray from the norm.

There is mixed and inconclusive evidence on which loads maximize athletic performance indicators (as well as mixed research on what load maximizes peak power for the various lifts). The best load is most likely specific to the individual and could have much to do with the individual’s “weak link.” For example, if they’re weak but pretty elastic perhaps you should try to get them strong, and if they’re strong but not explosive, perhaps you should focus on power and reactive strength.

It’s important to consider the fact that squatting and jump squatting motions aren’t biomechanically similar to sprinting so the correlation with advanced athletes may be relatively weak. Power is just one quality; there’s also speed, agility, endurance, skill, strength, etc. In sports, there are many different force-velocity relationships, so it’s wise to pay attention to different types of strength and loads. It appears that combined training and training with mixed loads is superior to uni-dimensional training and training at a single load. Some lifts lend themselves better to heavy lifting and some lifts lend themselves better to explosive lifting…perhaps it’s best to just train squats and bench press heavy, Olympic lifts relatively heavy (which means explosively), jump squats a little lighter and more explosively, and use sprints, plyos, and ballistics for the primary “rapid stimulus.” This ensures that you hit all the points on the force-velocity curve.

Finally, variety and periodization are important considerations in program design. With the many types of plyometrics, ballistics, sprint drills, towing drills, explosive lifts, and heavy lifts, there’s no reason to stick with solely one load (as a percentage of 1RM) indefinitely.

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Okay readers, I’m going to try to pack this interview with as much content as possible, so we’ll dive right into things! Matt Brughelli is a PhD researcher who studies biomechanics, strength training, and sport training. He’s a heck of a smart guy. He recently published a study that examined the effects of running velocity on running kinetics and kinematics. His findings have created quite a stir in the strength & conditioning and track & field worlds. Here we go!

1. Matt, what in the hell is going on? Did sprint researchers and track & field coaches have it all wrong? Your study shows that as running speed increases, vertical oscillation of center of mass decreases and horizontal forces increases at a faster rate than vertical forces. This indicates that horizontal force production is probably more important than vertical force production as speed increases. Doesn’t this fly in the face of the famous Weyand study? Did Weyand do something wrong? What gives?

First I would like to say that everything I’ve written in this interview is my opinion alone. I do not speak for my co-authors or anyone else involved in this study.

Hi Bret, lots of great questions here. I’d like to start with the relationship between vertical ground reaction forces (GRF’s) and maximum running velocity. Then I’ll give my take on Weyand et al. 2000, and will address the questions on horizontal force and “did they have it all wrong” in questions 5 and 7.

I think there is now overwhelming evidence that maximum running velocity is not limited by vertical GRF’s. With the addition of my recent study, there are now three studies that have directly investigated the effects of running velocity on vertical GRF’s over a range of velocities up to maximum (Brughelli et al. 2010; Kuitunen et al. 2002; Nummela et al. 2007). Each study used an athletic population and reported that vertical GRF’s (i.e. peak and average GRF’s) remained constant after reaching ~70% maximum velocity. This is direct evidence against the claim that maximum running velocity is limited by vertical GRF’s.

In addition, take a look at Table 1 in Chang and Kram, 2006. Vertical GRF’s were measured over different running curvatures (i.e. similar to a 200m sprint). Here, maximum running velocities were decreased due to the curvature. But vertical GRF’s did not significantly decrease until running velocities dropped below 60% maximum (i.e. inside leg only). This would also suggest that maximum running velocity is not limited with vertical GRF’s.

In regards to the famous Peter Weyand study (Weyand et al. 2000), I actually like this study very much. I have a lot of respect for Professor Weyand and consider him an expert on sprint mechanics. However, I think they (i.e. Weyand and colleagues) made very strong conclusions based on the quality of their methodology. They had a heterogeneous group of subjects (i.e. 24 men and 9 women; recreationally active; ages 18 to 36; no sprinting background) run at maximum velocities on a motorized treadmill that could measure vertical GRF’s. Then they performed linear regressions between maximum running velocities and ground support forces (i.e. average vertical force during the contact phase, relative to body mass). It should be noted that correlations and linear regressions do not imply “cause and effect”. As far as methodological quality, they rank relatively low.

I am in complete agreement with Karl Zelik (Buckley et al. 2010) that correlations and linear regressions should not be used as a surrogate for fundamental mechanical understanding of speed limitations. Instead of making such strong conclusions, I think Weyand and colleagues should have embraced the shortcomings and limitations of their study in order to motivate further research.

One more study I wanted to mention. Peter Weyand has published a new study in the Journal of Applied Physiology (Weyand et al. 2010) on the same topic. In this study, forward hopping and backward running were compared with maximum running velocity. Weyand and colleagues concluded that maximum running velocity is NOT limited by vertical ground support forces. Instead they propose that maximum running velocity is limited by the time required to produce ground support forces, which they argue is more due to muscle contractile kinetics.

One last point. Look at Figure 3 in Weyand et al. 2010. There are 6 subjects running over a range of velocities. With five of the six subjects (E was the exception, and the slowest runner), vertical ground support forces remain constant above ~7.0 m/s. This is very similar to the literature I have presented above.

Despite all of the above, Weyand et al. 2000 did find that faster runners produce significantly greater ground support forces in comparison with slower runners. So vertical GRF’s most likely do have some minor role in maximum running velocity. My only argument here is that maximum running velocity is not LIMITED by vertical GRF’s or ground support forces.

2. Matt, I’m going to be devil’s advocate here and attempt to cast serious doubt on your research. Please defend yourself. First, your study used a non-motorized Woodway treadmill which required sprinters to exert more horizontal force than regular overground sprinting since the belt slows down due to friction.

I don’t think friction is a problem with the Woodway treadmill. It’s possible. I don’t know of any studies comparing non-motorized treadmills for friction. According to the manufacturer, the Woodway uses a low friction bearing system that uses two bearing rails. Thus the decks do not need to be flipped like a conventional treadmill. I think if horizontal forces were increased (in comparison with overground sprinting) it would more likely be due to the tether as you mention in question 3.

I’d also like to point out that non-motorized treadmills have been shown to be valid in comparison with overground running for maximum running velocity. They have also been shown to have similar running kinetics or kinematics to overground running, and have excellent reliability. In a side note, Weyand et al. 2000 used a “motorized” force treadmill. Motorized force treadmills have been shown to alter running kinematics compared with overground running (McKenna et al. 2007)

You might wonder why researchers use treadmills at all. Why not use force plates mounted in the ground? Well its not easy to use force plates with subjects running at maximum velocity. And you only get a single step with a single force plate (if you are lucky) for each maximum running effort. With force treadmills you can get as many steps as you want. This is a HUGE advantage for researchers. Also, as Weyand et al. 2000 pointed out you do not need to deal with air resistance with treadmills. Faster runners would have greater air resistance in comparison with slower runners. There are always limitations, even when doing research with overground sprinting.

3. Second, you used a cable tether that exerted a rearward pull and therefore required more horizontal force production in comparison to regular overground sprinting.

As mentioned in question 2, it is possible that non-motorized treadmills create greater horizontal forces in comparison with overground running. However, if this was the case then you would expect two things to occur: 1) the studies on overground running would report less horizontal force in comparison with the studies using non-motorized treadmills; and, 2) the percentage of horizontal to vertical force production would be different between overground and non-motorized treadmill studies. This is clearly not the case. The studies using non-motorized treadmills have reported very similar, or lower, values for horizontal force in comparison with overground running (~400 N) at maximum velocity. And the percentage of horizontal to vertical forces is also very similar (~20%). Thus it is not likely that the tether is increasing horizontal force production during sprinting.

4. Third, net horizontal force at constant velocities are zero. I guess now you’re suggesting that Sir Isaac Newton was wrong?

Not at all. As I’ve mentioned in the previous questions, several researchers have used non-motorized force treadmills during running. My study is not novel in this sense, and none of us are breaking any of Newton’s laws.

It’s true that net horizontal forces are zero at constant velocities. This does not mean they are insignificant. Most studies only report peak propulsive forces and not braking forces. Most non-motorized force treadmills do not measure horizontal GRF’s. The horizontal forces are measured from a load cell that is attached to the tether. So braking forces are not measured. I was measuring vertical GRF’s from the force plate (i.e. four strain gauges) under the belt, and horizontal forces from the load cell attached to the tether. Again, this is nothing crazy or novel. Researchers have been using these machines since at least 1984 (Lakomy et al. 1984).

5. Forth, don’t you think you’re making some pretty ballsy claims for a single study!

Actually, I think my conclusions were very conservative. Most conclusions use terminology such as “these findings suggest that” or “we conclude that”. Lets take a look at my conclusion. First I said “it would seem”. This is not ballsy. Then I said “may be more dependent”. “Maybe” is not a term of great ballsiness. I did not say that horizontal forces limit maximum running velocity. In fact, I did not make any claim about any variable limiting maximum running velocity. I simply said that sprinting ability might be more dependent on horizontal forces in comparison with vertical forces. Again, “in comparison with vertical forces”. This is definably not a strong conclusion. It is not likely that vertical GRF’s have a major influence on maximum running velocity. So I feel these conclusions were conservative, but yet appropriate.

My conclusions were based on my own findings, and my understanding of the previous literature. They were not based on a single study. Both Nummela et al. 2007 and Kuitunen et al. 2002 also reported that horizontal forces significantly increase up to maximum running velocities. In addition, Nummela et al. 2007 and Brughelli et al. 2010 reported significant correlations between maximum running velocity and horizontal forces (r = 0.66 and r = 0.47), but not vertical. So my interpretation of these findings is that horizontal forces may be more important than vertical GRF’s for maximum running velocity.

For comparison take a look at the conclusions in Weyand et al. 2000, then look at the conclusions in Weyand et al. 2010. You tell me who makes ballsy claims.

I’d also like to say that I am not the first to make this conclusion about horizontal vs. vertical forces. Nummela et al. 2007 made a stronger conclusion that I did, as well as Randell et al. 2010. In addition, a few researchers have contacted me about my conclusion, and have mentioned that it supports their recent findings. So you will be seeing more papers in the next few years discussing horizontal vs. vertical force.

6. Moving along, based on your expertise, do we know what limits maximal speed production? What are some of the possibilities?

No one currently knows what limits maximum running velocity. I agree more with Weyand et al. 2010 that it could be due to the “time” side of the curve as opposed to the “force” side. Giovanni Cavagna has done some very interesting work in this area as well. I think that the time available to produce high forces is very important. In addition, I think horizontal force production is very important. So maybe some combination of the two.

I have a few ideas for more research on the limitations on maximum running velocity. However, after that I will probably never visit the topic again. I think constant velocity running is not very practical for most athletes. I think we are all missing the boat on this one. Why is there so much time and effort spend on this topic? How often does a soccer player, or rugby or basketball player run at a constant velocity? We need to go in other directions if we want to progress the field.

7. In light of this research, are you wondering if traditional methods of strength & conditioning might “leave something on the table” in terms of maximum acceleration and speed?

This is a very important question. I do think that traditional strength and conditioning (S&C) can improve speed and acceleration. However, I do NOT think the improvements are due to greater vertical GRF’s during running. I think Weyand et al. 2010 has made a very strong case for this point. In their new study they have reported that runners apply sub-maximal forces (i.e. vertical GRF’s and extensor muscle forces) during maximum velocity running. So I doubt if you improve an athletes squat, he/she will produce greater vertical or extensor muscle forces during running. I would like to see someone do a correlation between squat strength and vertical GRF’s during maximum velocity running. I doubt there would be any relationship.

Thus I feel that traditional S&C improves performance through other adaptations than vertical force production during maximum velocity running. I think these adaptations could include favorable changes in rate of force development, being able to maintain high force levels for longer periods, inter and/or intra-muscular coordination, etc.

I think coaches should be excited by the recent findings about vertical forces, and be open to implementing additional training methods for improving speed, acceleration and overall athletic performance. I think coaches should start implementing more horizontal strength and power exercises, hip extension/hyper-extension exercises, proper eccentric exercises, and continue to implement single-leg exercises.

Yuri Verkhoshansky introduced several examples of complex training in the famous Steven Fleck article (Fleck, 1986). Many of these examples complexed traditional vertical exercises with horizontal exercises. It’s an easy way to implement horizontal strength and power exercises into S&C programs. And now we have more exercises to choose from. Why not complex a squat with a horizontal weighted jump, or a squat jump with 30m sprints, or your hip thrust with 10m falling accelerations. The variations are endless. And this training is much more fun for the athletes. AND periodization becomes much more fun for the coach with complex training.

So in conclusion, I do not think traditional S&C exercises should be thrown out. I think they should be complexed with: horizontal strength and power exercises; hip extensor/hyper-extensor exercises; single-leg exercises, etc. I think eccentric exercise should also be considered for improving sprint and acceleration. Especially exercises that eccentrically contract the hamstrings during hip flexion, and eccentrically contract the hip flexors during hip extension/hyper-extension. But that’s another topic for another day.

8. What are some things that you’re excited about in strength & conditioning as well as biomechanics research? Where future research do you believe will positively impact athletic development?

There are a few areas in S&C and biomechanics that are wide open for research. And very practical areas as well. I think acceleration, deceleration and change of direction are very exciting areas. With these movements, the braking and propulsive forces are not equally balanced. Thus the muscle-tendons units act very differently during constant velocity “bouncing” gaits and acceleration/deceleration/COD. I also think a lot of great biomechanics research can be done on horizontal movements, and developing methods of improving horizontal force and power. Eccentric exercise is another very interesting area of research. Not just for muscle injury prevention but also for athletic performance. General injury prevention and analyzing leg asymmetries and deficits is also very interesting. Biomechanics of movement deficiencies (i.e. individual or sport/movement-related deficiencies) is another interesting area. So many different areas to still explore!

9. Matt, talk about the barbell hip thrust, how it differs from the squat, and how it might lead to increases in acceleration sprinting more so than maximal speed.

I love this exercise, and the other variations as well. With the hip thrust, the hip extensors are trained all the way through the end ranges of hip extension and hip hyper-extension. The moment arm of the glutes increases with hip extension/hyper-extension. Thus we need to find ways of training the glutes as the hip extends and hyper-extends. I think it is possible that the hip thrusts could improve hip strength throughout the end ranges of hip extension and into hip hyper-extension.

To me, this is the biggest difference with the squat. With the squat, the greatest benefits occur during the bottom position as the muscles are at longer lengths and switch from eccentric to concentric contractions. At the bottom position, the hips are behind the load increasing the moment arm from the vertical position. As you ascend from the bottom position and the hips extend, this moment arm decreases. Thus the hip extensors are not trained throughout the end ranges of hip extension and hyper-extension with the squat. Bands may help a little with this, but not much due to the position on the hips in relation to the load during the end ranges of hip extension.

Thus I think the hip thrusts would have a much greater effect on horizontal movements (i.e. in comparison with squats). I also think the hip thrusts would have a greater effect on acceleration than constant velocity sprinting. During acceleration, the braking forces are greatly reduced and propulsive forces are increased. The hip extensor muscles are required to produce power during acceleration. So it is important to find methods of improving muscle power of the hip extensors during athletic movements. I think the hip thrusts might be able to accomplish this, along with horizontal strength and power exercises.

10. Thank you very much for the interview! Last question. What does the future hold for Matt Brughelli?

Thanks for the opportunity Bret! The future is going to hold a whole lot more research. I will begin a post-doctorate research position in Belgium in a few months. I have several colleagues in Europe and am very excited about the coming years. There’s still so much to learn and I hope to be successful as a researcher in the future.

References

Brughelli et al. 2010. Effects of running velocity on running kinetics and kinematics. Journal of Strength and Conditioning Research, (Epub).

Buckley et al. 2010. Comments on Point: Counterpoint: Artificial limbs do/do not make artificially fast running speeds possible. J Appl Physiol 108: 1016-1018

Chang & Kram, 2007. Limitations to maximum running speed on flat curves. J Exp Biol 210: 971–982.

Fleck, 1986. Complex Training. NSCA Journal. 8(5): 66-68

Kuitunen et al. 2002. Knee and angle joint stiffness in sprint runners. Med Sci Sports Exerc 34: 166–173.

Lakomy, 1984. An ergometer for measuring the power generated during sprinting. J Physiol 33: 354.

McKenna et al. 2007. A comparison of sprinting kinematics on two types of treadmill and over-ground. Scand J Med Sci Sports 17: 649–655.

Nummela et al. 2007. Factors related to top running speed and economy. Int J Sports Med 28: 655–661

Weyand et al. 2000. Faster top running speeds are achieved with greater ground forces not more rapid leg movements. J Appl Physiol 89: 1991–1999

Weyand et al. 2010. The biological limits to running speed are imposed from the ground up. J Appl Physiol 108: 950 – 961.

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Usually when you hear the term “stiffness” in strength training you conjure up negative associations, for example tight muscles, poor posture, and restricted movement. Another type of stiffness can occur when you encounter something like this (see pic) but that kind of stiffness is not appropriate for this blog.

In the world of sprint and jump biomechanics, “stiffness” and “compliance” refer to the amount of deformation of an object (ie: muscles, tendons, fascia, etc.) in relation to the amount of force acting on the object. Stiff materials are hard to deform while compliant materials are easy to deform. An athlete can be both flexible and able to demonstrate considerable stiffness. A deflated basketball is compliant because it deforms considerably upon landing, whereas a golf ball is stiff because it does not deform much upon landing and is more “springy.” Elite athletes display more stiffness than novice athletes as their joints tend to move less when they come into contact with the ground when jumping and sprinting.

Increased stiffness is usually a good thing. Athletes adjust their level of stiffness depending on the task and surface. Here are some of the effects of increased stiffness (usually the effects are positive however as seen in point number five stiffness can be detrimental):

1. Increase cadence or bouncing frequency
2. Decrease ground contact time
3. Decrease ROM in legs
4. Possibly increase peak force and RFD
5. Possibly reduce impulse

Stiffness contains structural and contractile components, which means that tissues can adapt to become more stiff and muscles can contract faster and harder to create more stiffness.

In biomechanics the two most common types of stiffness measured are leg stiffness and vertical stiffness. Leg stiffness can be calculated mathematically by dividing the ground reaction force (GRF) by the change in movement of the leg range of motion (ROM). Vertical stiffness can be calculated by dividing the GRF by the change in vertical movement of the center of mass (COM). Leg stiffness and vertical stiffness are equal during vertical hopping tests (pure axial vectors), but not equal in cyclical actions such as sprinting (anteroposterior vector component). The reactive strength index (RSI) is calculated by dividing the height of a jump by the ground contact time. The height of the jump is proportional to the flight time. For this reason, RSI and leg spring stiffness are closely associated. See the pics below for an illustration regarding stiffness.

For a great video on stiffness, click here.

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