ISSUE #18

 

INSIDE THIS ISSUE…

-“Simultaneous Training for Strength and Endurance”
-“ACL Injuries and the Female Athlete”
-“Knee Injuries: Facts & Rehabilitation”

 

 

1 – SIMULTANEOUS TRAINING FOR STRENGTH AND ENDURANCE

 

Research suggests that concurrent strength & endurance training will interfere with strength gains. This may be due to overtraining (an excessive frequency or volume of training) or it may be due to the contrasting physiological adaptations that occur at the level of the muscle fibers (specifically, the contractile proteins).

 

The research designs of supporting studies are typical of an extreme athletic training regimen and may not reflect the average training routine (i.e. these studies sometimes trained legs > 3x’s per week in addition to aerobic training > 3x’s per week). The excessive volume of training alone may account for the impaired strength gains, although upper body strength has also been shown to be impaired in individuals training for both strength and endurance simultaneously.

 

Surprisingly, concurrent training does not appear to impair endurance performance. Heavy resistance training performed in addition to high-intensity endurance training does not appear to impair improvements in aerobic power, in fact, it is recommended that all endurance athletes include some resistance training (1-2 total body workouts per week) in their programs to increase muscle strength and to prevent injury. It is a great form of cross training!

 

For individuals seeking improvements in both strength & endurance, it is recommended that the training program concentrate on one adaptation at a time. For example, design a program to attain a desired level of strength and maintain the current levels of endurance. Once the strength is attained, the volume of strength training can decrease, but be sure to keep the intensity of training very high in order to maintain strength levels.

 

 

2 – ACL INJURIES: A HURDLE IN WOMEN’S SPORT

 

The Anterior Cruciate Ligament (ACL) is one of the most important ligaments in the knee and runs from the posterior tibia (shin) to the femur (bone of the thigh). Its role is to prevent the femur from moving forward over the knee (such as in knee hyperextension).

 

For example, when landing off-balance from a slam-dunk, a basketball player might have momentum attempt to force the femur forwards, but the ACL prevents this. A torn ACL occurs when a stress occurs to the knee causing hyperextension at the knee joint (i.e. rapid cuts, stops, or landing). 

 

The incidence of ACL injuries is much higher in females and a 1999 report broadcast on CNN claimed that there were 2 gender differences that may account for this phenomenon. First, females appear to land in a more vulnerable position while males tend to land in what is referred to as the “athletic” OR “ready” position. The “athletic” position is characterized by a significant bend at the knee joint (“quarter-squat position”), thus reducing the impact forces and torque at the knee joint.

 

Second, females appear to have insufficient strength in the hamstrings needed to stabilize the knee upon landing. However, these differences may not be the only reasons for a greater incidence of ACL injuries and in fact, may not account for the differences at all! Since an ACL injury is likely multi-factorial, all aspects of anatomy and biomechanics must be considered as issues, and should be addressed in training and coaching programs.

 

In order to remedy the gender difference in ACL injury reported by CNN females need to increase the strength of the hamstrings and to improve balance and landing technique. Team coaches and strength coaches should integrate exercises such as knee-flexion jumps, landing with a “toe-to-heel” pattern, and 180-degree jumps (single-leg plyometrics).

 

Strength training exercises should include deadlifts, forward and reverse lunges, and squatting. Not only will these strength exercises strengthen the muscles specific to the landing movement but they will also increase the athlete’s sense of balance due to the neuromuscular demands of proper exercise technique.

 

Female (and male) athletes may further reduce their risk of ACL injury by learning how to move more “athletically”. This includes bending the knees more when running (the “athletic position”) and as mentioned earlier, landing with bent knees. Women have been reported as have the tendency to run with an erect posture placing greater force on the quadriceps and less on the hamstrings (hamstring protects the joint by bringing the tibia back).

 

Many athletic injuries occur due to a misstep, rather than collision, so the incorporation of speed-agility-quickness and plyometric drills are warranted for all athletes in preparation for competition. All in all, total athletic development requires hard work in the weight room, in sport-specific pre-season drills, and on the practice field!

 

 

3 – GENERAL INFORMATION ON KNEE INJURIES

 

Strengthening the quadriceps and hamstrings with exercises such as squats, deadlifts, and lunges should help prevent injury. Never hyperextend or lock-out the knee joint during any leg exercise as this places unnecessary stress on the joints and removes the stimulus from the muscle. After developing a base level of strength with these exercises, and provided the athletes is injury-free, athletes should then begin jump or “plyometric” training to prepare and strengthen the knee joint for more sport-specific stress. 

 

Warming up prior to activity is essential and is rarely done in excess. Begin the warm-up with a light intensity of the planned activity (i.e. light jogging prior to basketball). A specific warm-up will lubricate the joints specific to exercise, loosens the active muscles, and raises the muscle temperature. All warm-up activities should be as specific as possible to the planned workout exercise (i.e. include side-shuffles for basketball).

 

Pre-workout stretching should be included to further prepare the tissue and joints. After the workout or game, stretching should be performed to help increase the flexibility of the exercised muscles. As well, schedule appropriate rest days to allow joint recovery and muscle repair, otherwise chronic overuse could lead to cumulative muscle damage and an acute injury in the future. 

 

If an injury should occur, it is essential to apply the basic RICE treatment immediately. Rest the muscle or joint and avoid any irritating movement. Ice the injured area, compress the tissue, and elevate the injury as well. The entire RICE protocol is recommended during the very acute stages of injury (24-48 hours) in order to reduce swelling, inflammation, and tissue necrosis (i.e. death to muscle fibers).

 

Tissue necrosis leads to scar tissue, therefore it is very important to minimize this process after any acute injury or any time a chronic injury is aggravated. During rehabilitation, it is very helpful to determine a limit for activity. Know when to stop (i.e. at a point where proper exercise or running form is lost) and if pain continues to persist after exercise has been stopped, it may require medical examination. 

 

Single-leg exercises should be the emphasis of any post-injury strength training (regardless of the seriousness of the injury). “Bilateral movements” (i.e. squat, leg press, & deadlift) train both legs simultaneously and are beneficial but have limitations. For example, if a strength imbalance exists after the injury, there will be a tendency to "shift" the load to the strong side during the performance of these “bilateral exercises”, thus furthering the strength imbalance. 

 

So, plan to use unilateral movements (i.e. single-leg exercises) and apply these tips:

·         Do the weak or injured side first.

·         Then, MAYBE do the strong side, BUT/ use the same load and perform only the same number of repetitions as were performed by the injured side.

·         If the imbalance is greater than 10%, do a lower ratio of reps on the strong side to the weak side. If the weak side can only do 10 reps, do only 5 reps on the strong side (OR 2 sets on the weak side to 1 set on the strong side).

·         If the strength imbalance is greater than 50%, consider doing no work on the strong side at all.

 

Do not do any exercise if it causes pain or discomfort to the joint.  Modify a painful exercise using the following tips:

·         Reduce the load OR the ROM.

·         Slow the speed of movement down.

·         Use both legs to lift the weight, then lower only with the injured side.

·         Delete the exercise and select an appropriate alternative.

 

Hopefully this will help you rehabilitate any present knee injuries OR prevent the occurrence of any injuries in the future.