Running is a very popular form of exercise. Running regularly can dramatically improve your health, satisfy the competitive spirit, build camaraderie, and give you a sense of accomplishment. With these clear benefits of running also comes risk of injury. In fact, running is associated with a high incidence of injury. This runner’s resource guide will provide many helpful and evidence-based tips on preventing running injuries and running healthier, stronger, and faster.
WHY DO YOU RUN?
• Many different reasons motivate people to go running: fitness, weight loss, clearing the mind, spending time with friends, meeting new people, accomplishing a goal, or for competition.
• Scientific studies have shown that running reduces risk of musculoskeletal pain, disability, stroke, and hypertension, improves bone density, and improves cognition and mood (1-5).
• Running is flexible – it can be done anywhere and anytime, with very little equipment.
RUNNING INJURIES ARE COMMON
Running Injury Risk
• Risk of injury is very high – according to a systematic review of scientific studies, as high as 79% of runners develop some form of injury (6).
• The body areas most prone to injury, as well as examples of the common injuries are:
- Knee – patellofemoral pain syndrome, iliotibial band friction syndrome
- Lower leg – medial tibial stress syndrome (shin splints), Achilles tendinopathy
- Foot – plantar fasciopathy, metatarsal stress fracture
- Hip/thigh/pelvis – labral tear, femoroacetabular impingement, trochanteric bursitis, gluteus medius tendinopathy
• Injuries span from minor ones requiring a short rest to major ones requiring long-term recovery.
• Every runner and every running injury is unique. You may be a teenager preparing for a 5k race, an office worker running for fitness after work, or a senior ultramarathoner recovering from a 100k trail run.
• Depending on your physical condition, running environment, and your goals, your risk of injury and projected time of recovery may be very different.
Long-Term Consequences of Running
• Studies have shown that runners are no more likely than non-runners to develop knee or hip osteoarthritis (7,8). On the contrary, running may protect your knee cartilage from thinning.
• Runners who sustained a previous ligament, meniscus, or cartilage injury may be at an increased risk of developing osteoarthritis if they continue to run regularly.
Knowing that running comes with such a high risk of injury, is there anything we can do to prevent injury? The answer may lie in the scientific literature, which reveals specific risk factors for running injuries. If we can recognize factors that contribute to the development of injuries, we can be proactive in modifying those factors before injuries develop. Below is a stepwise guide to identifying those injury risk factors and strategies to act before injury happens.
• Before setting up a training program, ask yourself these questions:
- How long have you been running on a regular basis?
- How frequently and how much distance have you been running?
- What are your goals with running? Is it to run 3 miles two or three times a week to stay fit? Or is it to run a marathon 6 months from now?
• Novice runners (< 3 years of experience) are at increased risk of injury9. This is likely because a beginner’s body is not yet adapted to the demands of running.
• Your body – particularly your bones, muscles, and tendons – goes through an adaptation process every time you run. The more times you impose the repetitive loading on your body, the stronger, stiffer, more coordinated, and more efficient your body becomes. In effect, you are getting fit to run.
• If you are a beginner runner not used to running on a regular basis, it is a good idea to follow a program to ease your body into the routine of running.
• If you can regularly walk 30-60 minutes briskly, you are ready to progress through this beginner program. By the end of this program even a totally novice runner should be ready to prepare for a 5k.
• Make sure to keep the run portions very comfortable. Adjust your pace so that you feel that you are running at 60-70% of maximal effort. If you are unable to easily maintain a conversation, you are going too fast.
• Run for 30 minutes on any 4 days of the week that are most convenient for you. Repeat the run/walk intervals throughout the entire 30 minute period as directed below. If you feel that you are struggling with the running, drop back to an earlier week’s program, until you can accomplish it without being out of breath before increasing the stage again.
• By the end of this program even a totally novice runner should be ready to prepare for a 5k. At week 12, runners keeping a pace of 10-12 minutes per mile will be covering 3-3 ½ miles during their “long” runs and 2-3 miles, most days of the week.
How to Progress From Here
• This program may satisfy your running goals. However, if you want to further increase your fitness, you can add more work, progressively.
• Add a few minutes each day till you can comfortably run 30 minutes on all 4 running days. Stick with that distance for a few weeks, allowing your body to adjust and for the work to begin to feel relatively “easy”. Once the distances become comfortable you can add up to 10% more miles, or minutes, each week.
• Safe and effective running programs, regardless of the target distance, are designed to expose you GRADUALLY to the stress of running.
• The benefit of gradually exposing your body to increased load is that your bones, muscles, and tendons will have enough chance to respond to the overload by getting stronger.
• What happens if you increase your mileage too quickly? The overload would be too much for the body to handle, and injury ensues.
• Keep track of your running distance (mileage). How many miles (or kilometers) do you run each time? How many total miles are you running per week?
• How much increase in mileage is appropriate every week? The answer is not the same for every runner.
• If you are hoping to gain speed, for racing or overall fitness, there are a few common types of workouts that can be used to achieve your goal.
• Seriously training runners might do each of these workouts once weekly, making for 3 “hard” days of training.
• If you are just building up your training program, add one high intensity type of workout at a time. Spend a few weeks, or even months, getting accustomed to the increased stress before adding a second hard workout into your training schedule.
• Harder workouts are useful to increase your fitness and speed, but they also increase the risk of injury. Local running groups often have coaches to help oversee the workout and help you get started.
• Threshold training can be done anywhere, but intervals and reps require a measured course, usually a 400 meter track.
• These are often called tempo runs, and are meant to improve running efficiency.
• Running at about 85% effort, or about 85% of VO2max, which is reached at a pace that is 10-20 sec/mile slower than 10k race pace, or 20-30 seconds slower than 5K pace.
• Most seriously training runners do 3-6 miles at this pace, after a warm up. You can break it up into multiple 10-minute segments, with ONE minute recoveries between.
• These workouts are for aerobic capacity improvement.
• They are 400-1200 meters (1-3 laps on a track) at about 5k race pace, with recovery time equal to the time spent running the interval.
• For example, if you can run an 8 minute pace for 5K, you could do a workout consisting of 6 half miles, each at 4 minutes, with 4 minute, jogging, recoveries between intervals. Total distance covered in the intervals should not exceed 5km.
• Jack Daniels suggests that these intervals be done at a pace 6 seconds faster than 5K pace, per 400 meters. Typically, the distance is 200-400 m with jogging recoveries that last at least 4 times longer than the time spent running “hard”. Our hypothetical runner who completes 5K races at 8 minute pace would aim for a 400 pace of 1:54.
• You are a unique runner. Your individual anatomy, history, personality, and behavior all contribute to your success and risk of injury as a runner.
• Since running is both a repetitive and symmetrical (i.e., right and left sides do the same thing) activity, any small deficit or asymmetry in the body may become magnified when you repeat the same motion thousands of times in a single run.
Risk Factors for Specific Injuries
• The scientific literature reveals that certain factors contribute to the development of running injuries:
- Previous injury, especially in the past 1 year, increases your risk of additional injury (6)
- Weakness or tightness in hip muscles is related to runner’s knee (patellofemoral pain) (10)
- Excessive pronation in the ankle/foot while running is associated with medial tibial stress syndrome (shin splints), Achilles tendinopathy, posterior tibialis tendinopathy, and plantar fasciopathy (11-13)
- Low bone density, menstrual irregularities, and excessive crossover or striking the ground excessively hard while running contribute to development of stress fractures (14,15)
• Do any of the factors above apply to you? Good news – you can do something about these risk factors.
Exercises for Injury Prevention
Following are some recommended exercises to strengthen your hip and thigh muscles, maintain flexibility, and improve coordination.
When is it appropriate to do these exercises? These strengthening exercises are best done after a run or on a separate day.
Seated Hip Flexion. While seated at edge of bench or chair, raise one knee up 5 inches. Keep upright posture without leaning your upper body. Add weights around foot to add more resistance.
Standing Hip Abduction. Stand on one foot and kick other leg out to side 45 degrees. Avoid leaning upper body to side. Tie a loop of resistance band around both ankles or attach ankle to cable column to add more resistance.
Kneeling Hip Flexor Stretch. Put one leg back and up on a chair and other leg in front. Move hips forward until stretch is felt in front of hip. Keep an upright posture and abdominal muscles tight.
Forward Plank. Prop up on forearms and feet, and hold this position. Keep abdominal muscles tight and maintain a straight line from ankles to shoulders without arching your back. Avoid holding your breath. Start with 30 second hold and progress up to 3 minutes.
Wall Squat. Stand one foot away from the wall with feet shoulder width apart. Squat down and touch your buttocks on the wall.
Single Leg Wall Squat. Stand one foot away from the wall, balancing on one foot. Squat down on one foot and touch your buttocks on the wall. Keep your knee in alignment over your foot.
Does Stretching Before Running Help Prevent Injury?
• Although many runners do stretches before running, the scientific literature shows that this is not effective in preventing running injuries.
• Studies have shown that less flexible runners are more economical (i.e., energy-efficient) because their stiffer muscles and tendons are better able to store and release amounts of elastic energy during running (16,17). Therefore, it is not appropriate to do static stretching before a run.
• There are certain mechanical factors that predispose a runner to injuries. These factors include:
- Excessive pronation linked to soft tissue injuries (11,12)
- Excessive ground reaction force associated with stress fractures (15)
- Dynamic valgus knee alignment (knees pointing towards midline) leading to patellofemoral pain (18)
• Physical therapists can examine your running gait and identify these factors. Once the mechanical factors are identified, corrective exercises and gait retraining can be instituted to address these factors.
• There is no single “gold-standard” way to run, at least from the perspective of injury prevention. Observation of injury-free runners reveals that even elite runners have a wide variety of ways of running.
• Regardless of your current running style, if you are not injured, there is no reason to drastically change the way you are running.
• Avoid over-striding - where your foot lands in relation to the rest of your body influences how much force the ground exerts on your body. The further in front you land, the higher this impact, and therefore more stress your joints have to absorb with every step you take.
• Other than practicing to take shorter steps, you can also modify your cadence to avoid over-striding. Speed is a product of cadence (number of steps you take per unit of time) times your step length. Using this relationship, by increasing your cadence, you can decrease your step length, assuming that you are running at the same speed.
• By increasing your cadence by as little as 5%, you can decrease the stress on your body. The best way to train with a changed cadence is on the treadmill because you can run at a constant speed.
• Appropriate footwear can improve your alignment, loading patterns, and your injury risk. Wearing the right gear for the environment and weather is also important in maximizing your performance.
• The key to right fitting gear is knowing your anatomy and finding what you feel comfortable in.
• There are 4 main types of running shoes: minimalist, neutral, stability, and motion control.
• The single most important parameter which determines what category a pair of shoes falls into is the amount of arch support. Depending on your anatomy, you may need more or less support for your arch.
• Many people may recommend standing in one place and observing your arch height or looking at the footprint on the floor after stepping out of the shower (i.e., wet test). It may not be that simple.
• Scientific studies tell us that static alignment (how your arch looks in standing) is not a good predictor of your dynamic alignment (how your arch looks in running) (19,20).
• Pronation refers to the motion which occurs at the ankle and foot complex, where the longitudinal arch of your foot flattens when you put weight through your foot. Pronation helps to transfer energy between the ground and your body and functions as an important shock accommodator.
• After the foot flattens to transfer the shock of landing, the arch should start to lift up and make the foot more rigid to prepare for effective push off. This is referred to as supination.
• Both pronation and supination are natural occurrences in the running gait cycle. The trouble lies in situations where too much/too little pronation occurs, pronation starts too early/late, or it lasts too long to prevent the foot from supinating.
• Physical therapists can examine your alignment, flexibility, and strength. This can be done both statically and dynamically. Based on a physical therapy examination, most feet can be grossly classified into 4 categories. These categories, as well as recommended shoe types and devices for each are shown on the table.
• One thing to note is that there are no clear lines between these categories. Many people’s feet fall into variations among those categories.
• The most important factor is your comfort. When you try on shoes at a store, walk around, jump up and down, and do a little jog in place. Give them a test run on a treadmill, if it is available. Do you feel comfortable in them? That is the most important factor in finding the right pair of shoes for your feet.
• How about minimalist shoes? Minimalist shoes, by definition, have a low heel-to-toe height ratio, provide little arch support, and are light in weight. These shoes are designed to give you a barefoot feel.
• Minimalist shoes are most suited for runners who want to focus on their speed, run with a midfoot or forefoot landing style, and are of moderate to light body weight (body mass index ≤ 25).
• Because minimalist shoes are made of less material than traditional shoes, they often do not last for as many miles as traditional shoes do. This means that you would need to replace your minimalist shoes more often than you would traditional shoes.
• How often would you need to introduce a new pair of running shoes? The best guideline to go by is that you should change your shoes when you feel or see wear and tear in your shoes. It may be feeling more pressure in your feet as you are running, or seeing the bottom rubber sole wearing out or a hole in the upper mesh material. When it no longer feels right, it is time to buy a new pair of shoes.
• Running is a rigorous activity which comes with many aches and sores that are perfectly normal. How would you know which aches and pains you should be concerned about?
• These are common signs of real injury, for which you should stop and pay attention to:
- Pain is severe (> 4 on a scale from 1 to 10) or worsening as you run
- Pain does not get better within a few hours after running
- Pain appears in the same location every time you run
- You change your running form to avoid pain
• What do you need to do when you experience these signs of injury? First, seek the help of a medical professional, ideally a sports medicine physician, who would be able to accurately diagnose your injury.
• Once an injury diagnosis is made, runners are often referred to a physical therapist, who would evaluate your weaknesses, running form, and training program. While resting to help the injured body part heal, you can work to address the deficits (e.g., strength, flexibility, coordination) identified by the physical therapist.
• Many runners are nervous about breaking their running routine, feeling that they would lose their fitness. During this time, you can keep up your fitness by cross training, training in a pool, or continuing to run if it is determined by the physical therapist that it is safe to continue running. A physical therapist can guide you through the entire process until you are back in your running routine.
• Lastly, a very important part of your running program – not running. As you pound the pavement, your body – your bones, joints, muscles, tendons, and even your heart, lungs, and brain – experiences stress. If given adequate rest, your body would recover and you would return to your next run more fit, refreshed, and with full of energy.
• How much rest is necessary? This depends on your body in how fast it recovers and what your training schedule has been. Many experienced runners are able to run 7 days a week with little risk of injury. This is because their bodies have adapted over time to the stress of running and are able to recover sufficiently within the 24 hours or so between runs. Novice runners who are not used to running on consecutive days would need 48 hours for their body to recover and adapt to the stress of every run.
• Novice runners should only run every other day. In general, it is recommended to take 1-2 days of rest every week.
• What should you do on these rest days? For most runners, complete rest is recommended to avoid putting stress on the body. However, light running or cross training (heart rate no higher than 60% of max) for 20-30 minutes may be allowed on a rest day. Think of this day as your reward for the tough miles you put in during the rest of the week.
Some of what makes for a good – or poor – performance is out of our control. Weather, the competition, good or bad referee calls are things we have no control over. Nutrition, however, is controllable, and some nutrients have profound effects on our ability to exercise well. Among the nutrients that are known to affect performance are carbohydrate, fluid, and electrolytes (salts).
• The depletion of the body’s stores of carbohydrates, or glycogen, results in fatigue. Glycogen is found in the muscle, where it serves to directly fuel muscle contraction, and in the liver, where it supplies blood sugar.
• When glycogen stores run low, high intensity exercise cannot be maintained (21).
• If the athlete expects to exercise for more than 90 minutes, it may be helpful to “carbohydrate load” or supercompensate the muscle with glycogen prior to the performance (22).
• While endurance-trained athletes store about 50% more glycogen than sedentary individuals, carbohydrate loading can further increase glycogen to more than twice that of untrained individuals (23).
• Carbo-loading may be achieved in as little as one day if the diet contains very high amounts of carbohydrate. Bussau et al. found that eating a very high carbohydrate diet for 1 day, while engaging in no exercise, doubles the amount of stored glycogen (24).
• To carbo load, eat 4-5 grams of carb per pound of body weight, per day. A 150lb runner would need to eat 600-750 grams of carbohydrate.
• For reference sake, a large bowl of pasta (2 cups) provides only 344 calories from carbohydrate – carbo loading requires eating very large portions of high-carb foods, so do not fill up on fats.
• If the athlete cannot follow such a rigorous diet the day prior to their event, they can do so a few days earlier. The muscles will remain super-compensated, as long as a normal diet is followed and very little exercise is performed (25).
Carbohydrate during Exercise
When carbohydrate stores run low, the athlete may feel dull and sluggish, and have difficulty performing high levels of training (26). Runners who are experiencing such problems should examine their dietary intake of carbohydrate (27).
• Taking carbohydrates, i.e. sugars or starches, during exercise can extend the time you can exercise before fatigue sets in (28). This is true in long duration exercise such as running or cycling for hours, and in shorter, higher intensity events such as during repeated sprints (29). While solid food takes longer to be digested than does liquid, Lugo et al. found that both are effective in providing energy during exercise (30).
• Running may pose more challenges than does a gliding sport like cycling (31). Runners experience more nausea and diarrhea and those symptoms are more likely when highly concentrated foods or beverages are consumed (32), especially when fructose is the sugar. The best bet, to avoid distress, is to stick with beverages that are 4-8% carbohydrate, such as Powerade, Gatorade, etc.
• If the athlete is involved in heavy training on repeated days or in multiple same-day workouts, rapidly restoring glycogen is essential. To best do so, consume carbohydrates within 30 min after exercise and at 2-h intervals post workout.
• Dehydration leads to poor performances (33) and, if severe, can lead to heat illnesses (34). During exercise, the goal is to drink enough to offset sweat losses of water, without drinking in excess of true needs.
• Over-consumption of fluid has been associated with life-threatening hyponatremia (35), and current recommendations for fluid intake are cautious: limit weight loss (due to sweating) to no more than 2-3% of body weight but do not drink more than has been lost in sweat.
• Water is fine for lower intensity exercise that lasts less than an hour, but sports drinks are advantageous for longer sessions. To determine how much fluid is required to rehydrate after exercise, obtain pre and post-body weights. Drink 1-1.5 cups of fluid for each pound (0.5 kg) lost.
The market is glutted with supplements being sold to athletes. There are a few that are worthy of consideration.
• The nitrate in beet juice, often sold as a concentrate or “shots”, may make runners more efficient (36). By burning less energy they are able to improve performance (37). The beet juice should be consumed 3-5 hours prior to exercise. Other good dietary sources are celery, lettuce and spinach.
• Sour cherry juice has been repeatedly shown to improve recovery after damaging exercise, such as downhill running. Marathoners who drank sour cherry juice (Cheribundi) every day for 5 days prior to racing had less inflammation and better recovery of strength post-marathon than those who drank a placebo (38).
• Weigh yourself pre- and post-run to determine how much fluid you need to restore.
As with all sports advice, NEVER try something for the first time right before a race. Always experiment during training and make sure it works for you.
Beth Glace, MS
Takumi Fukunaga, DPT, SCS, ATC, CSCS
Ian Kremenic, MEng
Last update on 11/20/2015
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