Resistance Training For Juniors

At junior levels, training rightly focuses on the technical and tactical aspects of the game. Every now and then, however, a team will field several players that are stronger and faster than their peers. These players evince the observation that chronological age differs from developmental age. In other words, 15-year-old children will vary in the physical characteristics of height, weight, etc, and the athletic capabilities that are resultant. While these cannot be standardized, training can help each player, regardless of their chronological or developmental age, to compete at optimal levels.

Resistance training, plyometrics, high-intensity interval training (HIIT) and repeated sprint training (RST) can be used to achieve these optimal level. However, many parents are unsure of the safety of some these methods of training.

The UPDATED POSITION STATEMENT PAPER FROM THE NATIONAL STRENGTH AND CONDITIONING ASSOCIATION has the following statements:

"In a report, there was no evidence of either musculoskeletal injury or muscle necrosis (death of muscle tissue) after 14 weeks of progressive resistance training." (page 2)

"Youth resistance training, as with most physical activities, does carry with it some degree of inherent risk of musculoskeletal injury, yet this risk is no greater than many other sports and recreational activities in which children and adolescents regularly participate. In a prospective study that evaluated the incidence of sports-related injuries in school-aged youth over a 1-year period, resistance training resulted in 0.7% of 1576 injuries whereas football, basketball, and soccer resulted in approximately 19, 15, and 2%, respectively, of all injuries." (page 2)

"Because weightlifting movements involve more complex neural activation patterns than other resistance exercises, childhood may be the ideal time to develop the coordination and skill technique to perform these lifts correctly." (page 3)

"Another concern related to youth resistance training regards the safety and suitability of plyometric training... plyometric training conditions the body through dynamic movements, which involve a rapid eccentric muscle action that is immediately followed by a rapid concentric muscle action. When the stretching and shortening of a muscle are performed quickly, the force generated during the muscle action is greater than the force that would be generated if the muscle were not stretched immediately before the muscle action. The contention that age-appropriate plyometric training is unsafe for youth...is not supported by current research and clinical observations. Indeed, comprehensive resistance training programs that include plyometric exercises have been found to enhance movement biomechanics, improve functional abilities, and decrease the number of sports-related injuries in young athletes." The NSCA goes on to cite the playground game of hopscotch as plyometric in nature! 'This type of exercise, although game like in nature, actually conditions the body to increase speed of movement and improve power production." (page 3)

"A traditional area of concern related to youth resistance training is the potential for training-induced damage to the growth cartilage...Although children and adolescents are susceptible to injury to the growth cartilage, the potential for this type of injury may be less in a preadolescent child than in an adolescent because the growth cartilage may actually be stronger and more resistant to sheering type forces in younger children...To date, injury to the growth cartilage has not been reported in any prospective youth resistance training research study. Furthermore, there is no evidence to suggest that resistance training will negatively impact growth and maturation during childhood and adolescence." (page 3)

The document is 20 pages in length, including 258 references collected over 38 years (1972-2008). Here is the link for those who may be interested in reading it.

http://www.nsca-lift.org/Education/E-learning/Would-my-Youth-Athlete-Benefit-from-a-Strength-and-Conditioning-Coach-/

Hopefully, this will ease parents' minds, and address some of their concerns over some very important questions they may have had.

Thanks for helping us keep the game beautiful.

Hamstring Injury Prevention In Soccer Players

I was all alone, the ball at my feet. I had a man approaching, but to me that just meant he was leaving space somewhere. A looked over my shoulder and played a perfect, favoured back heel, and off my right-winger went. At the same time, I felt a twinge in my upper right hamstring and my hand was over it reflexively. I had pulled a hamstring. Like anybody else, I tried to walk it off, but to no avail. Ice, heat, rest, foam rolling, and stretching did nothing but tell me how badly I was hurt over the next few days.

While there is no one cause for hamstring injury in soccer players, some factors may be predictive of injury than others. Flexibility abnormalities (Witrouw, 2003), issues related to warm-up and fatigue have been reported as increasing the risk of hamstring strain. Verrall et al., (2005) believe that stretching can improve force absorption for a given length of muscle, thereby making the muscle more resistant to injury that occurs when the muscle is stretched. It has been suggested that strength imbalances play a particularly important role in injury (Crosier, 2004), as it was in my case.

In a study involving 462 professional players, Crosier et al., (2008) found that players with untreated strength imbalances, mostly between the quads and hamstrings, were found to be 4 to 5 times more likely to sustain a hamstring injury when compared with the normal group. They concluded that normalizing the strength profile significantly reduces injury frequency. It goes without saying that performance will be less than optimal in the presence of imbalances as well. Because of the high prevalence of hamstring injuries, a preventive bodyweight and, in time, weight-training program could be undertaken by all players. Programs must include specific sequences targeting increased hamstring strength, particularly in the eccentric mode.


The primary function of the hamstrings, particularly when running, is hip extension. It is the glutes, the hamstrings, and other muscles about the sacroiliac joint that propel the body forward. Thanks to Bret Contreras, I know now about load vector training. Simply put, when we run, our hips move from back to front, (anteroposterior direction), we shout train movements that emphasize that direction as well- remember the principle of specificity. Below are a few exercises that have been my mainstay since my injury and they will, hopefully, help players stay off the sidelines, because of non-contact hamstring injuries, at the very least. This is by no means a comprehensive list, but its a start!

Body weight Exercises

Nordic Hamstring Exercise- I have mentioned this exercise in a previous article. The importance of training the eccentric contraction of the hamstring cannot be overstated. This exercise in particular was included in FIFA's "11+" programme, which has produced such good results, the governing body recommends that it replace the regular warm-ups of players aged 14 and older. This video is from that programme's manual.

Swiss ball hamstring curls

Glute Bridge

Weight Training Exercises- these are for advanced players who have weight training history/experience. Do not attempt these otherwise!

Romanian Deadlifts

Kettlebell swings

Lying leg curls

Lying leg press (legs high on the plate)

Weighted back extensions

Hip thrusts- Since my own injury, I have been doing hip thrusts among my other exercises. Consequently, I have stronger glutes, and for that I am faster without having to worry my hamstring injury recurring. So in honor of the Glute Guy, here's a video of him demonstrating this move he has championed:

References

Croisier et al., (2008). Strength Imbalances and Prevention of Hamstring Injury in Professional Soccer Players. A Prospective Study. The American Journal of Sports Medicine, Vol. X, No. X

Witvrouw E, Danneels L, Asselman P, D’Have T, Cambier D., (2003). Muscle flexibility as a risk factor for developing muscle injuries in male professional soccer players: a prospective study. In Croisier et al., (2008). Strength Imbalances and Prevention of Hamstring Injury in Professional Soccer Players. A Prospective Study. The American Journal of Sports Medicine, Vol. X, No. X

Worrell TW., (1994). Factors associated with hamstring injuries: an approach to treatment and preventative measures. In Croisier et al., (2008). Strength Imbalances and Prevention of Hamstring Injury in Professional Soccer Players. A Prospective Study. The American Journal of Sports Medicine, Vol. X, No. X

Speed and Acceleration in Soccer

Whether it is the forward, collecting a defence splitting pass for a shot on goal, or the defender, trying to prevent that shot, speed is essential to the game. Stølen et al., (2005) recorded that a sprint bout occurs every 90 seconds or so, while high intensity running is separated by 70-second periods. Soccer is, however, a stochastic game, meaning that a player may or may not have to be this engaged in these activities in these specific ways. Still, it makes sense that he or she be well conditioned to do so, should it be required.

Many studies have been conducted in the recent past, with the investigators publishing data that shows that a minute percentage of the total distance covered by soccer players is maximal effort. Amidst different categorizations, technologies and parameters, studies have observed ^[1,4,5,8]  2.1–3.7%, 18.9%, 11.3% and 3% for the total distance covered in sprinting or quick running, considering total distances averaging over 10 000m in a game. According to Bangsbo, sprint speed approximately 30 km/h covered a total of about 400 m only. Notwithstanding, sprints comprise the most crucial moments of the game and “contribute directly to winning possession of the ball and to scoring or to conceding of goals.” (Little and Williams, 2005)

Moreover, an estimated 96% these sprints are less than 30m. Valquer et al., (1998) observed the São Paulo Futebol Clube, who were the top ranked team in the Brazilian national league at the time.

The obtained results were as follows:

Distance (m)	0-9.99	10-19.9	20-29.9	30-39.9	40-49.9	“50	TOTAL	Overall distance
Numbers Sprints	26.4	18.6	7.8	1.4	0.6	0.2	55.0	718.2
SD	5.86	6.23	3.65	1.19	0.51	0.22	12.76	269.7
Frequency	49.0	33.4	13.6	2.5	1.1	0.3	100
SD	9.65	5.32	3.68		1.66	0.74	0.45

Table 1. Frequency of sprints over several distances in elite Brazilian soccer players. Valquer et al., (1998)

The results highlight the importance of acceleration training. Acceleration is the rate of change in speed that allows a player to reach maximum velocity in the shortest possible time. If the majority of the sprints performed during a match are 10m or less, more emphasis must be placed on that aspect of speed development. Currently, tests over 40 yards are administered from a standing start. While there is validity in these results, players most often reach maximum speed from a “moving” start rather than a stationery one. Therefore, it is the change in velocity rather than the initiation of it, that is true acceleration. Cometti et al., (2001) showed that professional and amateur had similar 30m sprint performance, but differed in the former’s 10m times. Theirs were significantly lower, suggesting “the fastest players are, on average 1m ahead of the slowest ones after only 10m of sprint[ing].”

This more recent study, confirms these findings, focusing on the duration of the sprints as much as these report on the length/distance.

The game is not to the fast, but to those who can get fast the fastest!

For your viewing pleasure, one run LONGER than 10m. Enjoy!

Play beautiful!

References

1.    Ali A, Farrally M. A computer-video aided time motion analyses technique for match analysis. J Sports Med Phys Fit 1991; 31: 82–88

2.     Bangsbo J. In Di Salvo V et al. Motion Characteristics in Elite Level Soccer. Int J Sports Med 2007; 28: 222–227

3.     Cometti G, Maffiuletti NA, Pousson M, et al. Isokinetic strength and anaerobic power of elite, subelite and amateur French soccer players. Int J Sports Med 2001 Jan; 22 (1): 45-51

4.     Di Salvo V et al. Motion Characteristics in Elite Level Soccer. Int J Sports Med 2007; 28: 222–227

5.     Little, T., and A.G. Williams. Specificity of acceleration, maximum speed, and agility in professional soccer players. J. Strength Cond. Res. 19(1):76–78. 2005.

6.     Mayhew SR,Wenger HA. Time-motion analysis of professional soccer. J Hum Move Stud 1985; 11: 49–52

7.     Stølen, T; Chamari, K; Castagna, C and Wisløff U (2005). The Physiology of Soccer. Sports Med 35 (6): 501-536

8.     Valquer W, Barros TL, Sant’anna M. (1998) High intensity motion pattern analyses of Brazilian elite soccer players.

9.     Withers RT,Maricie Z,Wasilewski S, Kelly L.Match analyses of Australian professional soccer players. J Hum Move Stud 1982; 8: 159–176

Can You Afford Not To Learn From Zidane?

Sport scientists agree the most effective training is that which most closely mimics the conditions of competitive performance. Therefore, training must be based on the specific physiological and biomechanical requirements of players’ respective positions. This will ensure players are better able to execute tactically during the game.

Di Salvo et al., (2007), measured the distance covered, distance in possession of the ball (meters and %) by players of different positions. These figures were collected from “twenty Spanish Premier League matches and ten Champions League games [were] monitored in the 2002/2003 and 2003/2004 seasons,” “by means of 8 stable, synchronized cameras positioned at the top of Bernabeu Stadium.” This was the galactico era at Real Madrid.

Position	Total Distance (m)	Distance in possession (m)	%
CD	10 627	119 ± 67m	1.2 ± 0.6%
ED	11 410	220 ± 99m	1.9 ± 0.9%
CM	12 027	230 ± 92m	1.9 ± 0.8%
EM	11 990	286± 114m	2.4± 1.1%
F	11 254	212 ± 92m	1.9 ± 0.8%

Table1. Distances covered by players during a game in total, in possession and their percentage representation. CD= Central Defender; ED= External Defender; CM= Central Midfielder; EM= External Midfield, F= Forward. (Adapted from Di Salvo et al., 2007)

I have played soccer for almost 20 years, watched it for just as long. No experience from all that time prepared me for this- less than 2% of the total distance covered by a player during a game is with the ball. It is a basic observation, but it was still quite a shock to see it represented in figures.

A few more observations can be made which should inform the training of soccer players. Firstly, players in different position cover different total distances. Central midfield players covered the longest distance, which correlated with higher VO_2max values. The center backs covered almost 1.5km less although they too covered a significant distance. It goes without saying that these distances include multidirectional as well as several other movement patterns like jumping, dribbling, tackling, and shooting. So if players traveled, at most, 286± 114m equaling 2.4± 1.1% in possession, what are they doing in the other 10 000+ meters? I ask this obvious, almost silly question because I believe that answer should largely determine how players train. The other 98% or so is covered either in trying to retrieve possession or in supporting the player on the ball. In one word, space.

The galactico of galacticos, (in my opinion) was Zinedine Zidane. His first touch is legendary, and who can forget his goal against Bayer Leverkusen in the Champions League final of 2002? The Frenchman was a master at finding the opening space, whether he was receiving a pass or making one. There can be no illusions about him being the fastest player of the field, perhaps at any point in his career. However, what he lacked in speed, he made up for with vision. He used quick bursts to enter into space and, as he demanded that those around him see what he saw, the gaps he played the ball into often found someone filling them.

Defensively, the same concept of space allowed legends such as Paolo Maldini the longevity they enjoyed. By learning to anticipate where the ball might be played, and by pre-emptively occupying that space, or at least starting towards it, the 41-year old (when he finally retired) did not need to be as fast as younger opponents were. Some have gone as far as to say, Maldini made an average of one tackle every two games, positioning himself so that he could intercept a ball rather having to make the tackle.

Practice identifying the space around, between and over the opponents if necessary. Practice targeting your passes in those areas. Practice filling them to receive a pass. Acceleration training is important for soccer players. In fact, Di Salvo et al., (2007) also reported that sprints corresponded to an average distance of 19.3 ± 3.2 meters. It matters little if you are the fastest athlete over 40 yards, as is the length of the standard sprint test. It matters how quickly you can get out of the blocks to cover the distance, and get yourself on the ball.

To keep the beautiful game beautiful, we must do the simple things well.

References

Di Salvo V et al. Motion Characteristics in Elite Level Soccer … Int J Sports Med 2007; 28: 222–227

Principles That Will Make You A Better Athlete

ALL training must have an objective- to stimulate structural and functional adaptations to improve performance. If it doesn't, get rid of it. The following are basic exercise training principles that must underscore everything you do. Embrace them, and they will make you a better player.


Specificity

Years ago, I watched a swimming 'coach' start his practice with the team running laps around the pool. WHY? "To develop endurance," he said. Not only was he risking injury to the swimmers, they were not building any endurance. The body adapts to what you make it do. If you want to be better swimmer, swim, and if you want to be a better soccer player, play soccer. No matter your sport, practice the way you play. I am not saying there is no benefit to cross training, but 95% of your practice should be sport specific.

Progressive Overload

Because the body adapts, what you find challenging today will not be challenging next week. Develop a system of measuring your experience with a certain skill or exercise. As it gets easier, tweak it, or move on to another exercise to keep yourself challenged and stave off boredom. If you are challenged, you have the motivation to continue to practice until you gain mastery. There is a classic story of a guy who picked up a calf on his shoulders everyday since it was born. Each day, as it fed, it became heavier and he, because his load was heavier each day, progressively got stronger.

Individuality

Not everyone will respond to the same program in the same way. At base level, variables such as previous experience, injuries, training status, even mental status will differ. As such, each player must be treated as the unique individual they are. Unless there are insignificant differences in these variable, any competitions with regards to training should be with yourself. This is why it is valuable to test yourself at the beginning of a training regimen, enter into a program, then measure yourself again at its completion. Comparing your before and after scores will give you a true picture of your adaptations (as well as the effectiveness of the program) rather than comparing with someone else.


Reversibility


All adaptations are transient and will return to pre-training levels if you stop practicing/training. Structural changes, elements of exercise and metabolic capacities that you develop from those hours of hard work can be lost within a matter of weeks of detraining. The best way to limit this reversibility is to keep at it. I will talk about periodization in a future post. It is essential to get a good understanding of this so that you can effectively manipulate intensity and volume of exercise. That way, you avoid overtraining, but also reduce the effects of a long off-season which can be devastating. 


Be mindful of these principles all the time and you will be able to determine for yourself what works and what doesn't when it comes to training. I have been subject to teachers who knew nothing about the game, and these 'coaches' had us do things I'm appalled about now that I know better. I've also had coaches who played but did not embrace the science of training. They simply made us do what their coaches made them do. In combining the playing experience with the science, I want to help you be a better player.


Keep the game beautiful!

Why Stroke Volume Made Me Quit University Soccer

When I was in university, I tried out for the soccer team, but I quit after three sessions. We had a 2-hour session, and for the first 75 minutes, we ran around the field, and never touched a ball.  Even the goalkeeper ran with us. Would you have stayed?

All training should have an objective. If you're coaching based what you did when you played, because your coach told you to, and he did that because his coach told him to, it’s time to re-evaluate your methods. And for players, ask politely if your coach can explain the relevance of what he is asking you to do. I don't know about you, but I put in more effort when I know that what I am doing will actually make me a better player. So what is stroke volume, and what does it have to do with soccer? First, some basic cardiac physiology.

VO_2max is the maximal amount of oxygen consumption by the body during exercise. It is a product of heart rate (HR) and stroke volume (SV). Fitter athletes have a higher  VO_2max  than their counterparts.

VO_2max= HR_max x SV

HR_max stands for Maximum Heart Rate, and refers to the highest number of beats your heart produces in a minute. Go for a sprint, and measure your heart rate straight after. A general estimation of  HR_max  can be also calculated using the formula 220- age.

Stroke volume refers to the amount of blood your heart expels from its chambers with each beat.

HR_max is largely unchangeable, but research has shown that stroke volume is. Basically, if your heart can pumped more blood to the exercising muscles with each beat, you can play at a higher intensity or the same intensity for longer. Your ability to recover from a sprint bout, a series of tackles, etc., is enhanced. It is now known that there is NO PLATEAU in stroke volume in well trained athletes. This means as long as you continue to train appropriately, you can continue to improve (to a point, of course!)

Endurance training should be designed to improve stroke volume, rather than aimlessly running around the field. Because soccer is an intermittent sport, comprised of lots of stop-start activities, laps are pointless. Short intense bursts, including changes in direction and ball contact should be incorporated in training for endurance. The research supports this. 

In an unpublished observation, researchers found that work at 90-95% of HR_max  for 3-8 minutes was an "extremely effective" method for improving SV. Intervals were separated by 2-3 minutes of active recovery. Different protocols involving running uphill (Helgerud et al., 2001) as well as short sided games (Hoff et al.39) have been used to try to improve SV. Reilly (1994) showed that running with the ball increased the energy cost by an approximated 8% than when running without it. 

Small sided games mean more touches on the ball as well as increased SV

Consider also that soccer is inherently an intermittent sport. Games are won and lost by successful short bursts onto the ball or into space. Reilly and other authorities who have extensively studied the physiology of the game suggest that there is somewhere between 70 and 90 seconds between successive high intensity bouts in soccer. The rest of the time, players will be walking, jogging or running at a moderate speed. This suggests repeated sprint ability (RSA) rather than 75 minutes of running around the field.

Therefore, I propose the following for endurance training, adopting the principles these investigators have used: (Since this is in training, and the aim is still to develop RSA, rest periods are slightly longer so that each bout can be performed maximally.)

Basic Sprints:

4 x 30m sprint. Walk back to the start each time. Rest for 3 minutes and perform another set of 4.

Incorporating the ball:

4 x 40m sprint. run with the ball from the 30m mark to the end, turn back and continue sprinting. Leave the ball at the same 30m on your way back. Walk the rest of the way. Rest for three minutes, then perform another set of 4. 

Progress to picking up the ball at the 20m mark to increase contact with the ball and improve technical ability as well.

Keep the game beautiful!

References

Helgerud J, Engen LC, Wisløff U, et al. (2001) Aerobic endurance training improves soccer performance. Med Sci Sports Exerc. Nov; 33 (11): 1925-31

Hoff J, Wisløff U, Engen LC, et al. Soccer specific endurance training. Br J Sports Med 2002 Jun; 36 (3): 218-21 al., editors. Science and football. London: E&FN Spon, 1988:

Reilly T. Physiological aspects of soccer. Biol Sport 1994; 11:3-20.  In Stølen, T; Chamari, K; Castagna, C and Wisløff U (2005). The Physiology of Soccer. Sports Med 35 (6): 501-536

Stølen, T; Chamari, K; Castagna, C and Wisløff U (2005). The Physiology of Soccer. Sports Med 35 (6): 501-536

Wiebe CG, Gledhill N, Jamnik VK, et al. Exercise cardiac function in young through elderly endurance trained women. In Stølen, T; Chamari, K; Castagna, C and Wisløff U (2005). The Physiology of Soccer. Sports Med 35 (6): 501-536

Zhou B, Conlee RK, Jensen R, et al. (2001). Stroke volume does not plateau during graded exercise in elite male distance runners. In Stølen, T; Chamari, K; Castagna, C and Wisløff U (2005). The Physiology of Soccer. Sports Med 35 (6): 501-536