.Since I have been working with runners, it has left me in awe of some of the nutritional plans, or lack thereof, of so many runners. Disclaimer! I am not a registered dietician, however I am proficient at reading, interpreting, and sharing evidenced-based literature on exercise and sports nutrition, as well as exercise physiology. The latter is important for understanding energy (nutrition) consumption needs for peak performance and recovery, which go hand in hand. Without proper nutrition, one cannot achieve peak performance or recover between workouts to gain the benefits of their training, especially if it is long in duration and/or intensity.
In a time when lifestyle diets are becoming more prevalent; paleo, ketogenic, vegan, low/non-fat, etc., it is of utmost importance to understand that what the body requires for activities of daily living is different than what the body requires for sports performance and recovery. The paleo and ketogenic diet are often confused because they are both a low carbohydrate diet, with less than 10% of your daily calories come from carbohydrates. The paleo diet is higher in protein, while the ketogenic diet is higher in fat, at least 70% of daily calories from fat. The above diets, along with low/non-fat diets, are trending today, especially for weight loss, and some will argue adamantly for health benefits, real and assumed. But many runners, unknowingly are neglecting their bodies. There is a time and place for everything including when the low carb runner should be taking in carbs and when the vegan and non-fat runners are making sure they get enough protein and fat. This blog post will look at information to help runners make better nutritional choices towards their goal attainment. Our bodies store glycogen (carbohydrates) in our muscles and liver and have the capacity to store 400-600 grams of carbs which equates to 1600-2400 kcal (Fink et al., 2011). If you google how many calories you burn during a marathon, it is going to say about 100 calories per mile as an average, approximately 2600 kcal. During a marathon, the body will run out of fuel before it reaches the finish line and this is only one reason why people sometimes “hit the wall”. Therefore, real-time race day nutrition is important to keep your blood sugar up when your liver and muscles have reached depletion. It may come as a shock that the current recommendation (remember I share the info, not determine it) is to consume 30-60 grams of carbohydrates every hour of running up to two hours and even more for over 2.5 hours of running (Jeukendrup, 2014). The American College of Sports Medicine suggests 0.7 g of carbohydrate per kilogram of body weight. A 125lb runner requires 40 grams of carbohydrate per hour to keep her motor running during a race over an hour. It requires training the gut to tolerate this much carbohydrate if you aren’t used to it, but will not be covered in this blog post. Interestingly, the world’s best endurance runners’ diets consist of 10% protein, 13% fat, and 77% carbohydrate for the Kenyans and 13% protein, 23% fat, and 64% carbohydrates, for the Ethiopians. Although there are other factors that foster superior distance runners from East Africa, their macronutrient profile is not any different than their global competitors and are preferred for optimal training and competition at that level of competition (Wilber & Pitsiladis, 2012). Their diets are far from being low carbohydrate, high protein, or high fat. But they are competing at a level far greater than the recreational crowd. Carbohydrate utilization is intensity driven. I know most of my readers don’t know what their VO2max is, but the greater intensity that you are exercising, the greater utilization of energy from carbohydrate sources, which would be at or greater than 75% VO2max. Check out a heart rate conversion calculator at this web link: http://www.shapesense.com/fitness-exercise/calculators/heart-rate-and-percent-vo2max-conversion-calculator.aspx At lower intensity exercise, less than 70% VO2max, there is a shift in fuel utilization to fat as fuel. Fat cells, called adipocytes can store up to 90,000 kcals of energy. Say what? Remember, we can store 1600-2400 kcal of energy from carbohydrates, which is a limited source of fuel for the marathon runner, none the less the ultra-runner, but we essentially have an unlimited source of fat storage to help us go the distance. Don’t be confused, this isn’t excess body fat, but essential fat and the storage is the same whether someone has a low or high percentage of body fat. One must understand that fat is a major fuel source for muscle cells in low to moderate exercise and when we are at rest. The only problem is that we are not very efficient at burning fat as fuel during endurance exercise. Training the body to mobilize fat as fuel would allow sparing of some of the carbohydrate storage to push out or avoid that aspect of hitting the wall altogether by becoming “fat adapted”. There are nutritional strategies that can be utilized in endurance training, Fink et al. (2012), but will not be included in the current blog post. Contact me for more info. So far the take-aways are; fat is your friend, carbohydrates are the preferred source of fuel at greater intensity running, lifestyle diets that restrict carbohydrates or fats may not be the best for runners unless you are willing to play with different strategies and regardless of everything, race day fueling strategies reign supreme for performance. What was not mentioned? Protein as a source of fuel. Why? Protein is a horrible fuel (sorry paleo fans) and although the liver can convert non-carbohydrate sources such as proteins into glucose (carbohydrates) it is normally an end of the road situation, too little, too late to help with performance. Don’t get me wrong though; protein is essential for muscle protein synthesis (repair and building of muscle). Assuming someone doesn’t follow a lifestyle diet and is looking to be the best endurance runner he/she can be, what should their daily diet look like during training and what else should they know about those macronutrients? Carbohydrates: 6-10 g/kg of body weight depending on training load/intensity = 336-560 grams per day for the 125lb runner. In addition to what was already stated about carbohydrates, they also play a role in metabolizing fat as fuel and is also vital in brain function with depletion leading to confusion and delusions. Sound familiar ultra-runners? Protein: 1.2-2 g/kg of body weight per day = 67-112 grams per day for the 125lb runner. Protein is important for distance runners because repeated muscle contractions of constant running cause protein breakdown, therefore protein consumption helps maintain protein turnover/synthesis. Fat: 20-35% of daily calories should come from fat, which is essential in the diet for runners and non-runners. Fatty acids provide energy, produce hormones, and surround nerves to aid in proper nerve function and aid in the absorption of vitamins A, D, E, and K, which are all essential in bone strength and muscular function. Nutritional strategies are huge in goal attainment. I hope this information allows my readers to reflect on their past racing performances and clarifies what their limiting factor was, if their training was spot on, but performed poorly on race day. In addition, I hope it is equally enlightening to all the runners that have missed their goal time by seconds or have experienced poor running times since adopting a lifestyle diet. Fight ON! Coach Gina Runner Image: Chris Pangilinan References: Fink, H.H., Mikesky, A.E., & Burgoon, L.A. (2011). Practical applications in sports nutrition (3rd ed). Burlington, MA: Jones & Bartlett Learning. Jeukendrup, A. (2014). A step towards personalized sports nutrition: Carbohydrate intake during exercise. Sports Medicine, 44 (Suppl 1): S25–S33. Meyer T, Lucía A, Earnest C, & Kindermann W. (2005). A conceptual framework for performance diagnosis and training prescription from submaximal gas exchange parameters: Theory and application. International Journal of Sports Medicine, 26: S38-S48. Wilber, R. L. & Pitsiladis, Y. (2012). Kenyan and Ethiopian distance runners: What makes them so good? International Journal of Sports Physiology and Performance, 7, 92-102.
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If you have read the “about” on the runwithgina.com website or read my very first blog post, then you know that I sustained preventable stress fractures in both feet when training for my first marathon. Stress fractures are the result of both intrinsic and extrinsic factors. It is the intrinsic factors that I find interesting as a female runner and both factors interesting as a coach. Everyone should be made aware of what contributes to stress fractures in general, especially for parents of younger children that seem to be growing up in a time of more sedentary lifestyles vs my generation that was outside running and jumping, playing hop scotch, jumping rope, red rover, hide and seek, and kick the can, in addition to organized sports.
According to research, it is difficult to determine risk assessment for stress fractures because there are so many interrelated variables. Regardless, I feel like I, personally, have combed through the evidenced-based literature looking for the answers as to why I got stress fractures in both feet and more importantly, moving forward, looking for how I can make the safest recommendations to those that allow me to work with them or even those that just tune into my blog. The above is the fuel driving the current blog post. The most common site of stress fractures amongst running athletes are sustained in the tibia, navicular, and fifth metatarsal (Shindle et al., 2012). One clear cut risk factor for stress fractures is being female. It has been noted that females are 1.5-3.5 times more likely to sustain a stress fracture than males (Scofield & Hecht, 2012). This alone is due to multiple factors including, but not limited to, female athlete triad; low energy availability (not eating enough calories to support the energy expenditure), amenorrhea (absence of menstrual cycle), and low bone mineral density as seen in younger, competitive female endurance athletes as well as any female athlete whose sport fosters an environment of leanness or low body weight (keep that in mind, parents of young dancers and gymnasts). Although sports like running, dancing, and gymnastics have a bone bearing affect to them, which should strengthen bone, it is the lack of energy (calories) and female hormones associated with menstruating that create the lower bone mineral density, more susceptible to fracture in puberty age girls and young women. Otherwise, running, jumping, and hoping are excellent for bone health. Bone mineral density previously mentioned is a measure of bone mass. The unfortunate thing is that according to research, peak bone mineral density is acquired during pre-adolescence and peak bone mass has likely occurred by the second decade of life through bone bearing exercise in childhood (Scofield & Hecht, 2012). Think for one moment, how this might impact my fellow runners that take up running later in life but were inactive in their youth? Moving forward, how might this impact the young people of today that were born into the screen-time generation, where playing hours of video games and hours of watching YouTube/movies/television is the norm, as opposed to activities that include bone bearing? Just some food for thought folks, and another reason why the Run With Gina blog posts are applicable to multiple populations, so don’t forget to share with your friends! So, what about my stress fractures? They were in fact in the navicular bone of both feet, which were identified above as a common site of fracture in running athletes. The navicular bone, is the main insertion point of the posterior tibialis muscles, which creates the motion of inversion at the foot, but also resists the movement of eversion (think pronation) at the foot. Stress fracture occurrence has a high association with rearfoot eversion/pronation in the stance phase of running as perpetuated by an altered load distribution from tibial internal rotation (Milner et al., 2010). Ah ha! I feel like I’m a detective following a lead here. My posterior tibialis was not strong enough to resist the motion of eversion, but who is causing eversion? Why that is Mr. Peroneus Longus, of course, and he lives on the outer side of your lower leg and has a propensity to get overactive as one of the muscles of push-off during running and foot/ankle stabilization. But what structures cause internal rotation of the tibia? Believe it or not, the structures that accelerate tibial internal rotation all originate on the pelvis; medial hamstrings, sartorius, and gracilis. I know, I know those names may sound like a foreign language, but the point here is that stress fractures can occur at the foot from a motion that begins at the lumbo-pelvic-hip complex. Preventative and rehabilitative measures should focus on muscles at distant sites, not just at the site of fracture. What I hope is even more clear to those of you that have graced me with your reading presence through all my blog posts, is that my goal is not only to help runners improve their race performance, but remain injury resistant in an activity that is plagued by injury. The latter is not easy because injury prevention is poorly understood without an understanding of functional anatomy and biomechanics which most people don’t have. Unfortunately, this also true of most coaches at every level. One cannot become a better runner when sidelined by injury and that is a no-brainer. As far as the subject of stress fractures goes, the above is not an entire list of intrinsic factors and I didn’t even go into extrinsic factors. However, I must let it be known that one controllable extrinsic factor is the loading of mileage or how many times/miles in a week you run in relation to the weekend long run. It blows my mind to see weekend warriors -- people that run long on the weekend, but don’t run any miles on the weekdays to support it. That is just an accident waiting to happen for all kinds of issues, including stress fractures. Keep in mind, safety is no accident! Fight ON! Coach Gina References: Milner, C. E., Hamil, J., & Davis, I. S. (2010). Distinct hip and rearfoot kinematics in female runners with a history of tibial stress fracture. Journal of Orthopaedic & Sports Physical Therapy, 40(2), 59-66. Scofield, K. L., & Hecht, S. (2012). Bone health in endurance athletes: Runners, cyclists, and swimmers. Current Sports Medicine Reports, 11(6): 328-34. Shindle, M. K., Endo, Y., Warren, R. F., Lane, J. M., Helfet, D. L., Schwartz, E. N., & Ellis, S. J. (2012). Stress fractures about the tibia, foot, and ankle. Journal of American Academy of Orthoapaedic Surgeons, 20, 167-176. I frequently have runners tell me that they have bad running form and I always think to myself, “Well, have you ever seen me run? I look like I’m about to tackle someone because my posture is tucked in”. Does ideal running form really exist and is what was ideal 40 years ago still the same as today? These are questions that are debated within the scientific community and I will probably crush some spirits in a future blog about foot striking patterns, but for now, I just want to write about why arm movement is equally important to performance and injury prevention.
When I first started marathon training, I was frequently told not to allow my arms to cross the midline of my torso so much. The more I tried not to, the more I was told to stop crossing over; in my mind, I was fixing it, but in reality it wasn’t happening. I think we all know that the movement of arms during running coordinate with the movement of the legs. Whichever leg is driving forward, the opposite arm is driving forward and hopefully all the energy to run is being used in forward propulsion. Unfortunately, we have a couple of things working against us. First, the arms are moving from the shoulder joint, which is the most unstable of all joints in the body. It sacrifices stability for mobility and we typically have strength imbalances, which I see time and time again when I do movement screenings on my runners. Our second issue, which plays off the first issue are the postures we have developed thanks in part to modern conveniences. Have you ever heard the term “smartphone posture”? Even if you haven’t heard the term, I guarantee you see it every single day. In modern society, we commonly sit with a cell phone or tablet in front of us or on our lap with our arms extended (which is really the action of shoulder flexion), shoulders rolled in, and/or neck flexed. The posture I just explained is the position in which I have been sitting at work for the last 19 years. My body has learned to take the path of least resistance and I have a rounded shoulder posture and unfortunately, when I run, it makes my arms drive more across my body. This same posture is seen in video gamers, people that sit and work on a computer all day, people that spend a lot of time driving with their arms out in front of their body, and all of us that live life on our smartphone…a large portion of society today, but not of 40 years ago! To be more efficient runners, we need arm drive to be turned on and this is accomplished by a balance between the muscles in the front and the back of the shoulder joint. As mentioned earlier, the shoulder joint is the most mobile of all joints so there are several muscles that contribute to movement about the joint but the prime movers for flexion (arm driving forward) are the pectoral muscles and the prime movers for extension (arm driving backward) are the latissimus dorsi and posterior deltoid muscles. Get these puppies in balance folks! In addition to decreasing the forward momentum of the body if the arms aren’t driving efficiently, it will also allow for more twisting through the torso and pelvis. In a 2008 study by Pontzer and colleagues, control of arm swing during running was investigated in a passive arm swing model vs an active arm swing model. In the passive arm swing model, subjects were asked to fold their arms across their chest, which in turn also decreased the moment of inertia. It was noted in the passive arm swing model that there was a lot of upper body movement, but it was not from flexion and extension at the shoulder joint as observed in the active arm swing, but from rotation coming from the torso. In an active arm swing model, shoulder musculature drives arm swing, but equally important, the arms act as mass dampers, decreasing rotational movements of the torso. Low back pain anyone? Not only can the extra rotation of the torso cause low back pain when arms are not flexing and extending during running, observational research has measured larger joint angles at the hip, knee, and ankle when arm swing during running is not efficient (Miller et al., 2009). Not only is this not energy efficient, it puts the distance runner at greater risk of strain injuries. Check it out readers… I want you all to be the most efficient and injury free runners as possible. That is the point of my blog posts. That being said, I see a lot of runners taking part in group strength training programs/challenges and others that are also gym rats. Sometimes, what you do outside of running to enhance your fitness may impair your run performance. Keep that in mind and hopefully you are working with mindful trainers that can identify your imbalances before strength training already overactive muscles. If your primary goal is to improve your run performance, you must understand that it requires a balanced body from head to toe! Oh, if you do in fact see me running down the road, you will see my rounded shoulder posture, rotating torso, and I may look like I’m about to tackle you. I promise I won’t, maybe just a high five. But seriously, the chances of having a perfect running form is slim in today’s day and age. I am far from perfect, but I do try to talk the talk and walk the walk and want to pass on the best available information on so that you, my readers, and running enthusiasts can make the best decisions for your body. Fight ON! Coach Gina Runner Image: Becca Roane References: Miller, R., Caldwell, G, & Van Emmerik, R. (2009). Ground reaction force and lower extremity kinematics when running with suppressed arm swing. Journal of Biomechanical Engineering, 131(12), 121-125. Pontzer, H., Holloway IV, J. H., Raichen, D.A., & Lieberman, D. E. (2008). Control and function of arm swing in human walking and running. The Journal of Experimental Biology, 212, 523-534. Last week I wrote a blog post about core training and whether it helps with run performance enhancement. The big take away was that there is no evidence supporting a direct correlation between regular core exercise and run performance. However, doing core work stabilizes the spine and pelvis and aids in the transfer of energy from large to small body parts. When your foot strikes the ground in running, the ground reaction force shoots up your body and every joint segment of your body takes that force. For all my geeky readers, this is Newton’s 3rd Law of Motion, which states, “For every action there is an equal and opposite reaction”. With a weak core (and when muscle imbalances exist), the forces are poorly distributed (which by the way, the ground reaction force of running is 1.5-3 times body weight) and injury can ensue. When a runner needs to take time off from training due to injury, he/she misses valuable training adaptions that are “dose” dependent. The more you run, the more aerobic, physiological, and metabolic adaptions occur. Strong core = more likely to keep training = more adaptions = better performance. The equation IS NOT, strong core = better performance. It’s not that simple and neither is proper half and full marathon training which is time and dose dependent. Meaning all the appropriate doses need to take place at the right time during the training season to yield peak performance on race day and no sooner.
But I digress; If you didn’t read the entire blog post on core training last week, please do so to get the rest of the info on core training. This week I want to share what else research has supported as improving run performance, in addition to running. Plyometrics! That is right folks, dropping and jumping. In a study of talented and highly trained endurance runners, researchers assigned plyometric training prior to endurance training, twice a week consisting of countermovement jumps with arms and drop jumps at 20, 40, and 60 cm, for a six-week intervention. After the six-week experiment, the runners improved their pre-study 2.4 km time trial by 3.9% percent (Ramirez-Campillo et al., 2014). Okay, so let me break that down so it makes more sense. If someone could run 2.4 km (1.49 mi) at an 8:00 min/mi pace, his/her time for 1.49 miles could possibly improve by 28 seconds! It is important to note that explosive plyometric movements are taxing on the body and should not be done on consecutive days. In the study, the participants had 48 hours between plyometric sessions. My disclaimer here is that this type of supplementary training should also be done only in a healthy, non-injured state. If you have bum knees or an issue with your Achilles tendon, explosive movements at the foot and ankle complex is not an option for you. So how the heck does this mechanism work anyway? Plyometrics work the stretch-shortening cycle (SSC), which is basically a stretch of a muscle followed by an immediate shortening of the same muscle. For example, in the drop jumps, you simply step off the box and as your body is descending, your muscles are lengthening (stretch) and at forefoot contact (do not land on your heals), you explosively jump vertically for maximal height. Not only does this work the important muscles of push-off for running, the plantar flexor muscles, it also uses elastic strain energy in the tendon as recoil. Interaction between the two continuous structures (muscle and tendon) influence force transmission and energy storage and return (Romanov & Fletcher, 2007). Interestingly, research has supported that 52-60% of locomotion is generated by tendons and without elastic energy storage and return, oxygen consumption during running would be 30% higher (Magnusson et al., 2008). I don’t want to digress again, but take note, elastic strain energy is good and my yoga-loving running friends need to know that excessive yoga training can negatively affect the ability to store energy in the tendons and increase the oxygen cost of running, which in very basic terms, means it makes you a less economical runner. Oxygen consumption (use) is a measure of running economy. For those of you that have been following the Run With Gina blog posts on Facebook or just reading on runwithgina.com, please note that in the future I will have blog posts on run training. However, my entire brand is about half and full marathon training based around injury prevention and performance enhancement through education. Without education and understanding, one cannot make good training decisions and propel forward in what they enjoy. Achieving your best as a runner isn’t about pounding the pavement for miles and miles and trying to do it faster and faster every time you hit the pavement. It is a process, that takes both patience and persistence. Your body is a temple and should be respected in that way. Be good to your body in training and it will be good to you on race day. Variety in training is good folks and so is #runwithgina, designing customized virtual training plans here, there, and everywhere! Fight ON! Coach Gina Runner Image: Jackie Hill References: Magnusson, S. P., Narici, M. V., Maganaris, C. N., & Kjaer, M. (2008). Human tendon behavior and adaptation, in vivo. Journal of Physiology, 586(1), 71-81. Ramirez-Campillo, R., Alvarez, C., Hernandez-Olguin, C., Baez, E. B., Martinez, C.,…Izquierdo, M. (2014). Effects of plyometric training on endurance and explosive strength performance in competitive middle- and long-distance runners. The Journal of Strength and Conditioning Research, 28(1), 91-104. Romanov, N., & Fletcher, G. (2007). Runners do not push off the ground but fall forwards via a gravitational torque. Sports Biomechanics, 6(3), 432-452. Have you ever been told that you should work on your core to be a faster or an injury resistant runner? How true are those statements? How does one acquire a strong core…through a bunch of crunches? Oh wait, those are old school; maybe planks with different variations? That is what you have seen in the popular press, isn’t it? Interestingly, in 2013 Dr. Bliven, a functional anatomy professor at my graduate school, A.T. Still University, published a paper on core stability training and stated that despite the popularity of core training for injury prevention and performance enhancement, minimal supporting evidence exists.
If minimal supporting evidence exists, why am I blogging about this subject? I subscribe to a newsletter from a physical therapist, who also designs virtual marathon training programs, as I do. He was discussing core strength making you a faster runner, as a sales pitch for his core training program. He goes on to say that a 2009 study by Sato and Mokha determined that after 6-weeks of core training, their study group improved their 5k time by 2.7%. I first read the Sato and Mokha study back in 2012 and know that in addition to the core workouts, the study group compared to the control group started out weighing more and running less miles a week and some were “recreationally active”, not necessarily runners. The study is flawed because in addition to the core exercises, the subjects increased their running mileage over the six weeks and the performance improvement could be the result of increased training adaptions from the increased mileage. Now don’t get me wrong, core training is valuable. But understanding why you do it and what specifically to do is extremely powerful for compliance. Having a stable core can indirectly make you more injury resistant and increase your run performance, by allowing you to continue to train injury free and adapt to training and become a faster runner. There is not a cause and effect, but an association. The lumbo-pelvic-hip complex including the lumbar and thoracic spine make up the “core” with 29 different muscles connecting to the lumbo-pelvic-hip complex. These muscles are not only responsible for stabilization of the spine and pelvis, but aid in transfer of energy from large to small body parts during athletic endeavors, not just running. The list of these muscles that stabilize the lumbo-pelvic-hip complex is way too long (it includes our friend gluteus medius, by the way), so I want to focus on two muscles that work together, their closest friends (teamwork makes the dream work), and what exercises should be the focus of your core workouts. Transversus abdominis and multifidus are the dream team of stabilization for the lumbo-pelvic-hip complex. One on the front of the body and the other on the back of the body, they create a corset, along with the oblique muscles. Transversus abdominis is deep, under the rectus abdominis, falsely referred to as the “six pack”. If you didn’t know, it really is an “eight pack” and we all have it, just some of us have more fat tissue on top of it. The multifidus spans the entire length of the spine, but is thickest in the lumbar region (low back), stabilizing intervertebral motion without compromising spinal movements or generating torque. Low back pain anyone? Only 80% of the population suffers from low back pain at one time or the other throughout the year. Strong evidence supports decreasing the reoccurrence of low back pain by rehabilitating (exercising) the multifidus (MacDonald et al., 2006). So once again, this Run With Gina blog post is good info for your non-running friends too. Pass it along! I know what you are thinking…cut to the chase! What exercises have research shown to be most effective in specifically targeting the transversus abdominis, multifidus, obliques, and our friend gluteus medius? So here they are and if you aren’t familiar with the names, I suggest you look up links on YouTube; supine bridge, supine unilateral bridge, side bridge, plank, bird dog, stability ball roll out, and stability ball pike (Advanced -- must build up to pike). Not on this list: crunches! Stay tuned for next week’s blog post on what exercise can be done for six weeks and has been proven (cause and effect) to improve 2.5 k run time by almost 4% in mid and long-distance runners…not recreationally active individuals, but actual runners! Fight ON! Coach Gina Runner Image: Mikey Francisco References: Bliven, K. C. H. & Anderson, B. E. (2013). Core stability training for injury prevention. American Orthopaedic Society for Sports Medicine, 5(16), 514-522. MacDonald, D. A., Moseley, G. L., & Hodges, P. W. (2006). The lumbar multifidus: Does the evidence support clinical beliefs? Manual Therapy, 11, 254-263. Sato, K., & Mokha, M. (2009). Does core strength training influence running kinetics, lower-extremity stability and 5000-M performance in runners? Journal of Strength and Conditioning Research, 23(1), 133-140. |
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