This article examines ways that trainers and coaches can take steps in order to effectively reduce the risk of clients suffering a training-related injury.
The following is a peer-reviewed article Nick Tumminello coauthored with Dr. Jason Silvernail, who holds one of highest Physical Therapist positions in the US Army. It was originally published in the NSCA Personal Training Quarterly Journal, Vol 4, Issue 2.
Strength and conditioning helps to improve a plethora of health and fitness parameters, including managing weight; lowering the risk of disease, death, and functional limitations; and reducing the risk of sports injury (4,10,13,21,23,41). The best ability in training is the availability to do it in the first place. The personal trainer should not only train clients towards their goals, but do so in a way that allows individuals to continue training. This article will examine ways that personal trainers can take steps in order to effectively reduce the risk of clients suffering a training-related injury.
Injury risk factors and concerns often vary by sport (e.g., factors for swimmers are not the same as for soccer players) and body part (e.g., factors for anterior cruciate ligament [ACL] rupture are different than for low back pain). Strength and conditioning is a low-risk activity, but it is not a no-risk activity (17). The following strategies can help the personal trainer successfully use exercise to reduce the risk of injury in their clients.
INCONCLUSIVE INJURY PREVENTION STRATEGIES
First, it is important to review a couple of strategies that are commonly believed to be “well-established” methods of reducing injury risk.
A 2014 systematic review and meta-analysis of randomized controlled trials published in the British Journal of Sports Medicine looked at the effectiveness of exercise interventions to prevent sports injuries. The authors of this paper stated that, “our data do not support the use of stretching for injury prevention purposes, neither before nor after exercise,” (21). It is important to note that the effect estimate of stretching in this study corresponds to earlier reviews (12,42). These research findings do not say that nobody should use stretching in their strength and conditioning sessions. Stretching can be beneficial in several ways, such as increasing joint range of motion and improving one’s tolerance to stretching (33). However, stretching solely for injury prevention is likely misguided.
Several movement-based evaluation systems have been promoted to discover poor movement patterns that indicate increased risk of injury. While these approaches are well-intentioned, evidence continues to build that these scoring systems have limited ability to predict injury and that better scores do not necessarily mean better athletic performance (9,19,26,32,34). Proponents of movement screens argue that some evidence shows that using a cut-off score can identify those at higher risk of future injury (2,6). However, validity problems remain, for instance it is impossible to know if the score itself is helpful or if there are other explanations for the injury risk findings in some of those studies (2,6). One such explanation is that individuals with a current or recent injury—a known risk factor for future problems—will tend to score lower on such tests (48). This means that the lower score may just identify a known existing risk factor. These systems can certainly be useful in exercise prescription, but current evidence does not support using these systems as general injury prediction or prevention tools.
GENERAL PROGRAMMING STRATEGIES FOR REDUCING TRAINING-RELATED INJURY
When it comes to minimizing training-related injury, most people are already familiar with the saying “don’t overdo it.” Generally, it is commonly recommended to avoid exercises that tend to put the body into an awkward position (e.g., behind the neck pressing and behind the neck pull-downs) or loaded end-range spine movements. Although that advice is fine, there is far more practical advice that can be added. The following are a variety of general, practical strategies that a personal trainer can use immediately, along with the rationale for why they can help in reducing the risk of training-related injury.
WORK AROUND PAIN, NOT THROUGH IT
If an exercise hurts the client—for any reason—the personal trainer should find a modification or an alternative that does not hurt the client. This recommendation does not apply to the sensation of muscle fatigue. Instead, it applies to any aches and pains that exist outside the training session or flare up when the client performs certain movements. Such problem areas may simply need time to rest and heal, or they may be injuries to body parts that can no longer tolerate the same level of load and do not improve without appropriate care.
Either way, a personal trainer who has their client train through the pain is not helping the situation. Although this fact should be obvious, many athletes and personal trainers are stubborn and use exercises that cause pain—a practice that is more often rooted in habit and ego rather than evidence. Continuing to perform exercises that cause pain could very well make things worse and lead to further damage, changing a painful area from something a personal trainer can easily train around temporarily to an injury that is more debilitating.
AVOID FORCING END-RANGES OF MOTION IN THE SPINE AND JOINTS WHEN LIFTING
As a general rule, avoiding forced end-range joint and spine actions are typically advised when lifting heavy loads or using medium loads for high repetitions. Research has shown that as the spine reaches full flexion, such as when performing deadlifts with an excessively-rounded back, support of the spine shifts from the muscles to the disks and ligaments (27). Weight shifts in the fully flexed posture can be quite dramatic and can easily cause excessive shear load (29). In full spinal flexion, not only is anterior shear loading higher, but the spinal ligaments are also at a heightened risk of injury (28). Additionally, repetitive compressive loading of the spine can exceed tissue tolerance and cause injury (11). Therefore, maintaining a relatively neutral spine posture when lifting heavy loads is sound training advice.
When joints are moved to their end range of movement, the load shifts from the contracting muscle to the noncontractile connective tissue (e.g., ligaments, joint capsules). This is not ideal for two reasons: the exercise no longer provides as effective of a training load for the working muscles, and the client may injure the other connective tissues. Weight training helps build those connective tissues as well. Tissues respond positively to load by getting stronger over time. Personal trainers should not be afraid to load their clients; however, loading excessively at the end range of motion does not have a good risk-benefit ratio.
Joints function very well in their mid-ranges of motion, but also need some full range-of-motion activity in order to stay healthy and maintain their current range of movement. Yoga or mobility drills can serve as a nice complement to comprehensive resistance training workouts. Due to their low-load and slow-paced nature, many yoga moves and mobility exercises require the joints and spine to move into their end-range of motion. Additionally, yoga and mobility drills get the client to move in a manner that they usually do not in weight training. This can provide more variety of activity and help the client to not just get stronger and leaner, but also to get more mobile.
USE CARE WITH PREVIOUS INJURIES
Injury risk is usually increased in those with a previous injury (25,38,44,48). Clients should tell personal trainers about any previous injuries that they have sustained. Additionally, some other advice that may be useful for personal trainers include:
Progress load and volume carefully around injured areas.
Be especially careful with movements and positions that were part of the previous injury. For example, an athlete who injured his or her knee coming down from a jump in basketball should be careful on single-leg plyometric exercises.
Do not neglect injured areas; building strength around an injured joint is important. Specific training of injured areas helps prevent future injuries (22).
INCORPORATE SINGLE-LEG STRENGTH EXERCISES
A study that compared unilateral versus bilateral squat training for strength, sprints, and agility in rugby players found that rear elevated split squats were just as effective as back squats in improving measures of lower-body strength, 40-m speed, and change of direction (40). Another study also found that single-leg and double-leg training increased strength and decreased fatigue, with no differences between single-leg and double-leg results (37). Interestingly, this study also found that single-leg training did not decrease fatigue during double-leg repeated maximal voluntary contractions, and double-leg training did not decrease fatigue during single-leg repeated maximal voluntary contractions (35). In other words, although these results demonstrate that improvements in strength are similar between bilateral and unilateral training, the results also suggest that unilateral training does not decrease bilateral fatigue and vice versa.
Single-leg performance during sidestep cutting may be a better indicator of how an athlete will move in sport activities, and therefore, may be a better predictor of injury risk than bilateral drop jump testing (20). Although this example applies better to the sporting realm, the following studies can also be applied directly to the personal training realm. For example, a study suggested using single-leg performance to detect deficits in unilateral force development, while another study showed that a 15% or greater variance in closed-kinetic chain strength or movement control ability in single-limb performance between the right and left leg is a good indicator of increased injury risk (31,36). Additionally, because weakness and fatigue in single-leg landings have been shown to increase the risk of injury, it may be beneficial to regularly incorporate single-leg training exercise variations in a client’s program to improve single-leg control, strength, and strength endurance (3).
DO NOT PERFORM COMPLEX MOTOR SKILLS AND MOVEMENTS IN A FATIGUED STATE
As clients move through their workout, muscular fatigue builds. Many studies have demonstrated that fatigued trainees lose efficiency of movement. For example, fatigue-related changes have been found in the muscles around the shoulder and knee (3,7,8,18). Muscular fatigue is associated with biomechanical changes in loading response and mechanics that may lead to injury. It is important to note that these biomechanical changes do not necessarily lead to injury in every case; however, avoiding complex skills and movements while fatigued is a reasonable precaution. The practical implication is that it is safer to avoid fatiguing clients until the end of the workout and after they have done complex or explosive exercises that involve more motor skill, such as agility and speed activities, plyometrics, and weightlifting movements.
IMPROVE CONDITIONING LEVELS
Since fatigue is a risk factor in injuries, improving conditioning levels can help an individual become more resistant to fatigue, potentially lessening the risk of injury from fatigue. In several studies, those with low levels of conditioning have been found to be at a higher risk of sustaining an injury (5,14,24,46,48). Besides conditioning levels, total training load is emerging as a risk factor for injury (15). All training is an applied stress to the body. This stress causes the body to adapt by becoming stronger, bigger, or faster to account for the stress. Smart, individualized training is about applying enough stress to the body to make it adapt without applying too much stress and overloading the tissues to the point where they can become damaged. With this in mind, planned rest days throughout a training week, along with incorporating rest or active rest weeks (consisting of lower demand activities) between several weeks of hard training can help in avoiding too much overload or stress.
LESSEN OR ELIMINATE QUICK STARTS FOR SPRINTS
One commonly found injury in sports or training sessions is hamstring strains. This can occur when individuals explode off the starting line doing a quick start when beginning a sprint. To reduce the potential injury risk from quick starts, one can jog to the starting point and begin sprinting upon reaching the starting line. Doing this will prevent the person from going from a static position straight into a sprint. If training for a specific test or event that demands a sprint starting from a static position, the client should train specifically using quick starts. In such cases, personal trainers should simply use what they believe to be the minimum effective dose of quick starts in their training program. Then the personal trainer could mix in several repetitions that include the jogging start.
DO NOT SMOKE
It is commonly thought that smoking is generally bad for overall health; additionally, some studies have demonstrated that it can also be a risk factor for injury (5,16,45,48). Smoking is a consistent risk factor for poor recovery after injury and poor healing. Therefore, it is advised to avoid smoking, both to reduce injury risk and to improve recovery after an injury or surgery.
GET ENOUGH SLEEP
Sleep and its effect on health, illness, and athletic performance have become more prevalent in research lately. Are adolescent clients and athletes getting 9 – 10 hr of sleep per night? Are adult clients and athlete getting 7 – 8 hr of sleep per night? If not, they may be at an increased risk of sustaining an injury (30,39,43,47). Reviewing appropriate sleep guidelines with clients for enhancing performance and reducing injury is a solid evidence-based practice for personal trainers (1,39,47).
To sum up, the following are some basic suggestions that a personal trainer can adhere to in the effort of reducing the risk of injury in their clients:
- Train around, not through, pain problems
- Avoid extremes of motion under load in the spine and joints
- Use caution with previous injuries, but still train the injured area to improve resilience
- Program more single-leg strength exercises
- Perform complex motor skill exercises and movements in a relatively rested state
- Prioritize aerobic conditioning and manage training load with care
- Lessen or eliminate quick starts for sprinting and agility work
- Encourage smoking cessation in clients who smoke
- Make sleep management and sleep hygiene part of the training program
There are several potential risk factors for injury. It is important to remember that risk factors are not guarantees. Having one of these factors present does not doom a client to injury, while having none of them does not guarantee an injury-free future. These factors vary in predictive ability and relevance across different groups of people, and the recommendations here are considered a practical interpretation.
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