Jump Training

JUMP Training Marin is an injury prevention based program designed for girls and boys, 9 to 18 who are at least 4’10”.  Using 3 primary pieces of equipment Power Plate, Jump Cord and bioDensity, JUMP Training will teach young athletes how to become more efficient, effective and safe competitors.

Individual sessions can be scheduled as well.

Please call with questions. (415) 945-9778

Girls & the ACL Tear, Still a Mysterious Knee Injury

What you don’t know could hurt them but we have a solution.

It turns out that high-school-aged girls who play competitive soccer and basketball have more to fear than the other team.  In fact, it’s their own bodies that may be their biggest contender.
The contender’s name?  The Anterior Cruciate Ligament or ACL.  ACL tears are the most common injury for girls who participate in soccer and basketball, and during high school the risk of an ACL tear is 2 to 8 times greater for girls than boys. Any sport where girls are cutting—making lateral movements or jumping, puts them at risk.   While there have been dozens of studies and articles about this, there are still many unanswered questions.  Why do so many more girls tear their ACLs ? Why is there a rise in ACL injuries among girls entering puberty and a spike between 16-and 18-year-olds?  What can be done to prevent the injury?
What I know for sure is that EVERY parent who has a daughter who plays a sport that involves a lot of lateral movement and jumping needs to be aware of the prevalence of sports-related knee injuries in girls.  Orthopedic surgeons across the country call the situation “alarming” and an “epidemic.” In the United States 20,000 to 80,000 high school female athletes experience ACL injuries every year—most in soccer and basketball.  And while there are many unanswered questions and no single cause, there are interesting theories, and most importantly, prevention programs targeted toward reducing the risk of knee injuries in girls.
Body By X Skill Development & Training Center has developed a new ACL injury prevention program called JUMP Training Marin for Marin County athletes.  But first let me tell you what the ACL is, what it means to tear it, and what the current theories are.
Your ACL is no bigger than your little finger.  It’s a fiber, similar in texture to a rubber band.  It attaches to your femur or thighbone in your upper leg and to the tibia or shinbone in your lower leg.  Its purpose is to stabilize the knee.  What they call an ACL tear might better be named an ACL explosion.  When the ACL pulls apart from the femur and tibia it turns into a viscous liquid. Fifty percent of the time a pop accompanies the injury and, almost always, a scream.
The ligament must be replaced with a graft.  Part of the patellar or hamstring tendon is often used for this purpose.  Rehabilitation from an ACL tear is 6 to 12 months.  Sitting on the sidelines, missing out on play with friends, or not being able to help a team succeed is, for many girls, more painful than the injury itself.  For some girls, the injury is life changing.  Scholarships are lost or never gotten.
Two-thirds of ACL injuries are the result of a sudden change in direction, cutting movements, one-step/stop decelerations, landing from a jump with a straight or nearly straight leg or a lapse in concentration that is often the result of an unanticipated change of direction in the game.  In other words, they don’t involve coming into contact with anyone or any thing.
The Theories
The only thing researchers agree on when it comes to the prevalence of ACL tears in girls is that no single cause can be blamed, at least that cause has yet to be discovered.
Research has determined that the following things may be contributing factors and that the ultimate cause is likely multifaceted:
More Girls Playing Sports
Since the passage of Title IX in 1972, girls’ participation in high school sports has increased more than 900%!  Another way of looking at this astonishing statistic is to say that in 1972, 300,000 girls participated in high-school sports, in 2008 that number was 3 million! The sheer numbers alone explain some of the increase in ACL tears in girls.  It doesn’t explain the gender discrepancy.
In addition to the increase in high school female athletes—these same athletes play with far greater intensity each year.  We ask both boys and girls to step it up a few notches when they enter high school and yet we don’t consider the fact that physical differences may put girls at more risk.  Interestingly, injuries are seven times more likely to occur during a game than a practice!
Blessed with wide hips or not?  Wider hips mean girls are more knock-kneed and this anatomy of the knee makes female athletes more vulnerable. Wider hips also create a greater angle for the femur to come into contact with the tibia.  The greater the angle, the more stress there will be on the inner side of the knee.
Girls have smaller ACLs and smaller intercondylar notches which are the grooves in the femur through which the ACL travels—smaller also means more prone to injury.
Studies have identified gender differences when doing specific athletic movements—specifically landing from a jump or changing directions suddenly.  According to the Knee Injury Prevention Program (KIPP) in Ohio, Girls tend to demonstrate less activation of the hamstring muscles, less knee and hip flexion, and greater inward collapse of the knees than boys.
Many of the articles I read focused on the fact that boys naturally develop or perhaps instinctively know how to use their bodies when playing sports.  My husband, Xavier, described his own experience learning how to jump when at a young age he jumped out of a tree he had climbed.  The chill he felt reverberating through his legs taught him not to land from a jump with his legs fully extended EVER again. My son, Luca, shared a similar experience except he jumped off a playstructure.  I guess girls don’t jump from trees or playstructures!  An article in the Nicholas Institute of Sports Medicine and Athletic Trauma writes, Boys have historically been trained from an early age to use their body in sports activites.  Their training includes footwork drills, eye-hand coordination skills, catching and throwing balls which develop their neuromuscular systems.  Girls are not exposed to this early motor learning at a young age, putting them at a distinct disadvantage whem they decide to get involved in sports in high school.
It isn’t fair!  Testosterone makes high-school aged boys stronger with very little effort.  It also makes them less flexible.  Girls, on the other hand, have estrogen to thank for an increase in fat, not muscle.  Estrogen makes girls more flexible by making the ligaments more lax, and while flexibility is an asset in many arenas, insufficient muscle prevents the joints from being stable.
In 2009, Cincinnati Children’s Hospital published a study suggesting that because most high school aged girls add height and weight but comparatively little strength, they don’t have the power to control their taller, wider bodies.
According to an article in The Physician and Sportsmedicine, Estrogen has also been reported to decrease fine motor skills by acting on the central and peripheral nervous systems.   Deficits in motor skill may “diminish the normal neuromuscular protective mechanisms of the knee.”
Other studies have focused on the role of the menstrual cycle and ACL tears.  Nashville based orthopedic surgeon, Dr. Kurt Spindle, has done research on hormonal reasons for the high incidence of ACL tears in girls.  He discovered that girls were three times more likely to have an ACL tear when they were having their period.  Hormones enter the bloodstream during menstruation and come into contact with active hormone receptors on the ACL.  Spindle believes that a spike in hormone levels temporarily changes the composition of the ACL, leaving it more prone to tearing.  He showed that women taking oral contraceptives were less likely to tear their ACL because the contraceptives prevent hormones from being released into the bloodstream.   The findings are based on a small study group and their histories were relayed to medical staff so the validity is somewhat questioned.
Another group of researchers identified a trend toward an increase in injuries in femailes during the ovulatory phase and a decrease during the follicular phase,.  These researchers were not, however, able to conclusively identify a difference in injury rates as a function of the menstrual cycle.
No Breaks & Stiff Competition
Some doctors site no breaks between sports and playing a single sport year round as the primary cause for the epidemic.  Dr. Michael Willis, an orthopedic surgeon at Billings Clinic says the situation “isn’t that complicated.  With year-round and multi sport participation, many of our young athletes do not have time for recuperation, and injury potential increases dramatically.
According to Michael Sokolove, author of Warrior Girls, Protecting our Daughters Against the Injury Epidemic in Women's Sports and a New York Times Columnist, writes, [This] divergence between the sexes occurs just at the moment when we increasingly ask more of young athletes, especially if they show talent:  play longer, play harder, play faster, play for higher stakes.  And we ask this of boys and girls equally—unmindful of physical differences.  The pressure to concentrate on a “Best” sport before even entering middle school—and to play it year round—is bad for all kids.  They wear down the same muscle groups day after day.  They have not time to rejuvenate, let alone get stronger.  By playing constantly, they multiply their risks and simply give themselves too many opportunities to get hurt.”
In March of 2010, a group of researchers and physicians attended the Fifth ACL Research Retreat.  The retreat strives to document and update a consensus statement on the cause and prevention of ACL injuries.  One of the areas of focus during that retreat was on risk factors and injury prevention.
Some researchers believe there are ways to determine if your daughter has a predisposition to an ACL tear.  One way is to simply look at how they move on the field or court.  As a result of better understanding what not to do—run upright, for example, or land from a jump with knees extended, a few injury prevention programs that focus primarily on neuromuscular retraining and biomechanics, have had success.  The KIPP program, reports that their participants are 9 times less likely to injure their ACL.  According to the Billings Gazette, a follow-up of preventive programs, like KIPP, that have been in place for more than 10 years shows a significant decrease in ACL tears in women.  Still the rates remain higher for girls than boys.
The American Journal of Sports Medicine declared that women who undergo lower extremity injury prevention workouts are 62 % less likely to suffer traumatic knee injuries.
To help Marin County kids avoid injury, improve their athletic form and performance, and to simply get stronger—that’s always a good thing for an athlete!—Body By X is launching the Jump Training Marin program in February 2012.
Jump Training Marin is an injury prevention based program designed for girls and boys 9 years old and up.  “We want to teach kids how to move their bodies safely while doing sports, and the sooner they learn the better,” says Marin County’s Body By X co-owner, Xavier McClinton, who will lead the training.  “Jump Training Marin will train young athletes to have proper form when jumping and running, strengthen their muscles and improve their balance,” Xavier says.
Jump Training Marin will focus on the neuromuscular and biomechanical differences in girls that are being blamed for the increase in ACL tears.  “We know we can’t change girls’ anatomies or the hormones they have, but we can give them the training they need and we can also enhance the training boys’ receive as a result of just being boys,” Xavier adds.
Proprioceptive exercises will be a large part of Jump Training Marin.  Proprioception is the ability to know where a body part is without having to look.  Think of how you can walk up a flight of stairs without having to peer at each stair.  Our body’s proprioceptors control balance, coordination and agility, so by improving ones proprioception, young athletes can gain balance skills necessary to maintain stability; sharpen their agility so they can change direction quickly; and better their coordination skills.  Proprioception exercises reduce the risk of injury by teaching the body to react appropriately to sudden changes, especially on a field or court where the changes are faster than ever.
JUMP will make hamstrings stronger and promote more knee and hip flexion. Marin County needs an injury prevention program to help athletic kids in our community play safely, and, hopefully, Body By X’s JUMP Training program will make the high rates of ACL tears in Marin County girls AND boys a thing of the past!
 JUMP Training Marin will rely on 3 primary pieces of equipment:
The Body By X Power Plate turns the neuromuscular system on to get maximum muscle activation and 100% recruitment of muscles.
The Jump Cord uses resistance to increase an athlete’s vertical jump.  You wear the jump cord and it works in unison with the body.
bioDensity technology:  this latest combination of the best in science and technology enhances sports performance safely by providing a self-induced neuromusculoskeletal loading stimulus.  Because the stimulus is self-applied, participants stay within their own comfort zone.  Additionally, the  biodensity machine forces proper biomechanical position so risk of injury is virtually eliminated.  The results?  Stronger bone tissue and increased muscular strength.
JUMP Training consists of 30-minute, one-on-one trainings twice a week for five weeks.  For more information or to schedule sessions for your child, call Body By X @ 415-945-9778.

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