Sports

Nature vs. Nurture

Nicole Lowe McBride2 Comments

We’ve all heard that the Kenyans are built for running-it’s in their genes. Statements like that raise more questions for me, such as: do genes(nature) limit my ability to improve my running? do my genes determine what type of training(nurture) or races I should do? How much of my improvement is from my pure stubbornness to succeed (is that genetic too?)?

I think it’s obvious that both genes and training play a role in our progress and ability in our sports. And I’m not sure if knowing which one is dominant is helpful because if it’s genes, the brain of many runners could get in the way of them making improvements through training hard due to a belief that they are limited.

There are more than 100 genes that have an impact on physical capacity. The belief that our genes determine our running performance seems reasonable, after all, our genes determine our body size and shape. Both of these influence our running performance. Those with smaller bone structures are going to be lighter on their feet. They are less likely to have non-propulsive muscle mass weighing them down.

Two measures scientists use for unraveling the nature vs. nurture questions are VO2 max and Lactate threshold. What they’ve discovered is that the degree to which VO2 max increases in response to exercise has a 47% genetic component. That leaves 53% friends-more than half. The degree to which Lactate threshold increases in response to exercise is a 55-80% genetic component. That’s a pretty big spread if you ask me.

How important is VO2 Max for ultrarunning? VO2 max is the highest rate at which your body can transport oxygen to your muscles, through blood, to provide your muscles with the energy they need. Most people can only sustain this level of effort for 8 minutes. Not helpful in an ultra that lasts up to 36 hours. Your VO2 max becomes less important as the distance of your run increases. This is not to say doing VO2 max training isn’t worth while. See my post on that here.

What about Lactate Threshold (LT)? LT is the point at which the level of lactate accumulating in your blood is higher than what your body can get rid of. During lower intensity exercise (ultrarunning by nature), lactate levels remain at or near resting levels- a steady state. Training your LT is still important. See my post referenced at the end of the last paragraph.

Other factors that determine running performance are diet, attitude toward running, daily activity pattern, amount of sleep, injuries, running efficiency, determination, and much more. What the science has concluded so far is there are just too many genes that impact sport performance to be able to predict who will be a good athlete and who will not.

So what can our genes tell us? no more than our personal experience which is the better route to go. Yes, there are companies out there who will test your DNA and tell you if you have a low, medium, or high aerobic potential, but I ask again does that really help you to know? I think this is a situation where ignorance is bliss. If we believe we have an insurmountable genetic limit, it will become a self-fulfilling prophecy.

I look out there at my fellow ultrarunners and I see the “impossible” accomplished at every race. Grit is a better predictor of our ability to succeed than any genetic test.

 

 

Block It

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We all get stuck in a rut, but it can be really easy to do with your workout routine. I know I’m guilty of this on multiple occasions, with both my running and with my strength workouts.  There are a few problems with the rut: first, you don’t make any progress; second, you lose motivation; third, it’s boring!

The first is the most important for runners who want to improve. Not all runners want to improve. They are content running their six miles four days a week at a comfortable pace. That’s not me. I want to get better and I like to see progress. Even if improvement isn’t your think, staying motivated to get out there and not being bored the entire time should be enough for you to want to change things up every few weeks.

Many runners work through their training in blocks. Blocks can be four, six or eight weeks long and during each block you focus on a different aspect of your running. That doesn’t mean you drop other aspects of training, they just aren’t the focus point. Other runners switch things around by every other week. And still others, do a rotation over a ten-day period.

Strength Blocks: Starting a block rotation with strength is great because the number one goal of strength training for runners is to reduce risk of injuries. There are three types of strength training typically used by runners. First is body weight. This uses light weights or no weights with high repetitions. The idea is it builds strength and stability without the mass. Second is plyometrics. Plyometrics are explosive movements, such as jumping and springing. These are great but need to be implemented in small dosages especially at the beginning. Third is heavy lifting. Heavy lifting is low repetitions and max weight which strengths your connective tissue. Lifts should be done very slow and controlled. You’re runs during a strength rotation should be lower in intensity because you’re kicking up the intensity with strength training.

Speed Blocks: during your speed block you’re going to have an intense speed workout once a week and then throw in some fartleks during your long run. For your weekly intense session, choose different types of work outs. Don’t just do 800s. There’s nothing wrong with doing a week of 800s, just don’t make it an every week thing. Use pyramids, tempo runs, ladders, or 400s.

Hill Blocks: during your hill block you will have one run a week dedicated to running hills and then you’ll throw in extra hills for your long run. You can run hill repeats or find a long steady climb to conquer. If you’re doing short repeats, walking the downhill is fine, but you’ll have to find some longer downhills to practice downhill running. Downhills will tear up your legs if you don’t build them into your training.

Build Blocks: As endurance runners, especially at ultra-distances, your long run is going to stay in the weekly rotation. However, if you’re not doing a build phase, you’ll only do one long run a week rather than the back to backs. You can also choose to run one long run and then the next day a ten-mile run. But if you’re not in a build block, you’re not increasing the miles on that second day.

The important part is that you are changing things and challenging your body in new ways. Using the same workouts doesn’t get you more of the same results. It gets you a flatline.

 

Training Races

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Now is the time to begin planning your race calendar for 2018. Many races fill up early, especially, trail races which have more restrictions on enrollment numbers. Plus, it’s fun. Once you have a list of races you’d like to do for next year, pick one as your goal race. This will be the race all of your training will be focused on. It does’t mean you can’t do other races; it just means the other races are training races.

What’s a training race? It’s a organized event that you run in which is not your goal race. Training races are very useful because they keep you engaged and motivated, but they do a lot more than that too. Let’s start with the motivation piece. Motivation waxes and wans through training, especially, if your goal race is months away or if you have a lot of rebuilding and thus a longer training plan. Having shorter races(compared to the goal race) along the way gives you small goals and accomplishments along the way.

The most important function of a training race is it tells you where you’re at in your training and where you need to go. But, for it to be able to do this, your training races have to have at least some of the same race conditions as your goal race. The distance of your training races will depend on the length of your training plan and the distance of your goal race. So, if your goal race is a marathon you’ll want to pick a 10k and half marathon. The half marathon should be about 4-5 weeks from your goal race. The 10k would be earlier. For a 50k you’d choose a marathon about 4 weeks before and maybe a half a month before that. For a 50 miler, you’ll choose a marathon and a 50k. The 50k being about 4 weeks from your goal race and the marathon 3-4 weeks before that. For a 100, You’ll want a 50 miler about 4-5 weeks before your goal race and a marathon 4-5 weeks before that. We’ll talk about adding more in a second, for now lets focus on these two training races.

For these two training races, you’ll want to decide how much effort you want to put into it. I’ll tell you right now, you shouldn’t be putting full race effort into them. About 75-80% is all you’ll want to do because you don’t want to risk injury, but you want to get a good idea of where you are and how your training is working for you. The other reason you don’t want to put in full effort is because it take a while for your body to recover from full race effort and you’ll need to get back to training after the race. This also makes timing of the training race important which is why the longer one should be about 4-5 week before your goal race.

For a training race to fulfill it’s purpose, the conditions need to be as close to your goal race as you can make them. This includes course and difficulty if you can. If it’s off a little don’t worry about it. The timing of the race is more important than matching your terrain exactly. The other part of “conditions” you’ll want to mimic are your prep. You need to prep like it’s your goal race. Practice your nutrition plan just like you’ll do in your goal race, pack drop bags (even if you won’t use them), use the gear you’ll be using in the goal race (even if you don’t need it all), eat your pre-race meal, do breakfast the same, and go to bed at the same time.

Can you do all this as just a regular training run and not do a training race? you can, but the race atmosphere changes things. It changes your mindset, your adrenaline levels, your competitive nature, and race day anxiety. those are hard to produce in a training run. It goes back to creating the same conditions as you’ll face at your goal race.

Tapering before a training race is different because you don’t want to kill your training four weeks before your goal race. However, you do want to do a mini taper and a mini recovery. Cut back your training the three days before the training race and take the day before as a rest day. After the race, take a two days rest and then do an easy run.

What about adding more races into your schedule? you certainly can, but they should be treated like a training run not a training race and certainly not a race. You can practice a lot of the things you’ll be doing at your goal race, but you shouldn’t run it any harder than you’d run a training run. This goes back to risking an injury and depleting your body to the point of it needing recovery days.

Happy planning!

Trail to Road

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Switching from road to trail running has its challenges, but so does switching from trail to road. First, you don’t want to run on the road with your trail shoes. Road shoes can be used on less technical trails and dirt roads. Trail shoes should not be worn on the road unless you are running a trail and have to cross the road to get to the next section. Roads and sidewalks will destroy the tread on your trail shoes. If you’re going to be running some roads, buy some road shoes or be prepared to replace your trail shoes after a few runs.

There is research out there, done by credible sources, which comes to the conclusion that the impact on your body is the same whether you run on the roads or on the trail. The theory is that your brain and your body automatically adjusts the stiffness of your legs and torso dependent on the firmness of the ground. When you’re on a trail you have to push off harder because it is a softer surface. On the road, your leg has to be less stiff and you don’t push off as hard because there is very little give in the ground.

I’ve read this research and my body disagrees. I can run a fifty-mile run on the trial and I will not be sore. If I run a marathon on the road, I will most definitely be sore the next day. Could it all be in my head? Sure, why not. The only way you’ll know if it’s true for you is to go try it.

One way to combat the soreness from running on the road is to buy high cushioned road shoes. There are a variety out there, just about every major brand of running shoe has both minimal and high cushion options. Keeping your stride length shorter will also help reduce the impact. Maintaining proper running form—head up, shoulders back, ninety-degree angle arms, nice forward and back swing without crossover, a bent knee and foot landing below you—will make sure the impact forces go through your body in the correct way.

The higher impact (in my opinion) of the roads also makes for a longer recovery between runs. Using your foam roller becomes extra important because you need to work out the knots and flush out the lactic acid which may have built up.

A few other differences are the level of pollution, number of people and cars. Out on the trail you have some critters and creatures out in the woods and some are a little scary if you run into them—mountain lion—but to me people are way more dangerous, and so are cars.

It is easier to find a toilet and to refill your water when you are running on the road. Although, a water filter and not being afraid to bare your bottom in the forest solve those problems.

I think we all run on both surfaces at some point. And there are enjoyable things about each of them. Being able to run is what matters most.

 

Trackers

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Runners like numbers. We want to know how far we’ve gone, how fast we were, how much we climbed/descended, what our heart rate was and on and on. As much as we love numbers, it’s also important to keep things in perspective and enjoy the run for the run, so leave your fun toys at home once in a while and just run.
If you’ve been in a sports store or a running store recently, I’m sure you’ve seen the numerous watches that track every bodily function and your place on the earth at each moment. There are a lot of options out there. When you are in the market I would suggest doing some research. Here are some starting points:
Keeping It Simple
Mio Slice ($100): this little guy tracks your heart rate and makes recommendations about how much activity you should be doing each day. It’s tracking is very accurate. You can track steps, distance, calories burned, and sleep. It’s compatible with iphones and android. Battery life is five days.
Polar M200 ($120-150): tracks heart rate, speed, distance, and route.  connects with an app you can download on your phone. It has a running program adjustable to your needs. Battery life is 6 hours in GPS mode.
Polar M400 ($130): does everything the M200 does plus tracks altitude, calories,  steps and sleep quality. It’s waterproof to be used in all weather conditions. it has a bigger numbers on the display and it’s battery life is 8 hours in GPS mode.
Going Big
Garmin Fenix 5S ($700): this guy comes in three sizes in case you have smaller wrists. It is a multisport tracker with a barometric altimeter, magnetic compass and wrist band heart rate monitor. It measures stride, cadence, ground contact time, bounce, and estimates your VO2 Max. Battery life 24 hours in GPS mode
Suunto Spartan Sport Wrist HR ($500): a multisport trainer, waterproof up to 100m. It has 80 pre-set modes and sport specific metrics. It tracks your basics such as location, pace, heart rate, speed, altitude. Battery life 12 hours in GPS mode (other models have longer battery life if needed such as the spartan ultra 26 hours).
Samsung Gear S3 Frontier ($300)
This one runs on 4G LTE, bluetooth and Wi-fi so you can take calls and respond to text messages without your phone nearby. It’s compatible with android and IOS. It tracks your altitude  distance, location, pace, heart rate and more. It’s water, dust, and extreme temperature resistant. Batter life up to three days with mixed use and screen set to turn on/off automatically

Losing it?

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One of the most frustrating things that happens when you take time off running is you lose your hard earned fitness and have to work your ass off to get it back. We all know the longer you have to take off of running the more you lose. This is definitely something I have struggled with as I’ve been coming back from two rolled ankles and a strained hamstring. Anyone who has been forced to take time off running due to an injury knows you go through the whole grief cycle, which I’ve written about and you can find it here.
There are two aspects of losing it: the mental side and the physical side. Let’s start with the easier of the two: the physical side. There’s been lots of research about how quickly fitness is lost when an athlete has to take time off after an injury or just because they are burnt out. We lose the most fitness right up front 20% in the first three weeks. Ouch. after that things level off and up to three months you retain 80% of your fitness. For those athletes who have trained for a long time the impact over time is less because you have a stronger base of fitness. What the experienced athletes lose is what they have most recently gained. You go back to your baseline. As much as this steep drop in fitness loss sucks, it is easier to get back to where you were than it was to get there in the first place.
You can slow the loss and maintain fitness by cross training that makes sure your aerobic system keeps working at the level you had it and doing strength training to minimize the amount of muscle strength you lose. Sport specific fitness is definitely going to take a  hit though so don’t get discouraged when you go back and are sore after a run that would have been a walk in the park pre-injury.
The mental side of it, in my opinion, is the harder of the two that you work through. Depending on how long you are injured, you may have developed a maladaptive coping skill telling yourself it doesn’t matter and maybe you do something other than running. Sometimes it can go as far as, I just don’t want to run anymore. Telling ourselves these things when there is no end in sight or we when we are catastrophizing is a way that we cope with the loss of running, which has becomes a indispensable part our life and who we see ourselves as.  The problem with this, is it makes reviving the motivation to get back out there more difficult. The best way to regain motivation is by remembering the things you love about running, which can trigger those feelings of loss all over again that you were trying to avoid in the first place. See my article on working through the cycle of grief link above.
Once you are back out there, you have to get over the fear of another injury. This takes time and building trust in your ability and self confidence. The only way to build these is to get out there. Give yourself permission to go at your own pace by taking it slow and run easier routes for a bit. It helps if you come up with a plan of action. A plan will help you come to terms with the fact that you can get back to where you were.
A critical element to maintaining motivation and avoiding a lot of self recrimination is to not compare yourself to where you were and where you are. This is a particularly difficult one for me. Try to remain positive and every time this thinking pattern pops into your head, counter act it by reminding yourself that you had to work hard to get to where you were and it’s possible to do it again because you know how and you know you are strong enough mentally and physically to get there. The other half of working through this is accepting where you are. Berating yourself and dwelling on the fitness you’ve lost is not going to help you move forward. It doesn’t change where your current level of fitness is at.
It is not easy to come back from an extended voluntary or involuntary break from running, but runners are a tenacious bunch who like challenges and this is just one more hill to climb.
I’ve also blogged about the safe way to return to running after an injury. You can find it here.
Here is a post about how to run in the swimming pool. Boo!
There is also something called forced rest depression which I talk about here.

What’s that sound?

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Wondering why your knees, ankles, wrists or fingers snap, crackle, and pop? The jury is out on the definitive reason why this occurs and is unlikely to come in with a verdict any time soon. One reason is the ligaments are stretching over a bone and slipping back in place. Second is the compression of nitrogen bubbles in the spaces of the joins and then the refilling of the joint with synovial fluid, which lubricates your joints. A third reason they could be popping is due to friction between the muscle/tendons and the bone. Tight muscles/tendons make this more likely to happen. A fourth reason is called joint fixation. This is when the bones of a joint become stuck together due to suction and when the seal is broken you hear a pop. You can tell the difference between friction and fixation by the reoccurrence rate of the popping. Fixation takes time to set up, so it won’t repeat with every bend of the joint. Friction on the other hand will repeat each time you bend the joint.
Everyone has popping joints at one point in their life or another. In most cases, there is enough slack in our tendons and muscles that no harm is done. Although the sound of it can be irritating or concerning, there is nothing to worry about injury wise. You’re not causing damage and it doesn’t mean that there’s an injury. You should be concerned about a pop is if it causes pain or swelling because it can indicate a tearing or rupture of a tendon or even a fracture of a bone. You will likely know if it could be something like this because there will be an event that causes it. If there is swelling and pain try rest, ice, compress and elevate. If that doesn’t help after three or four days or if the pain is serious(painful to use for normal daily activities) and there is significant bruising, see your doctor.
If the popping is driving you crazy, there are some things you can do to try to reduce or banish the popping. First, try some stretching of the tendons and muscles around the area where the popping is occurring. Stretching should be done when the muscles are warm and not to the point of pain only tightness. Be gentle with yourself. Hold a stretch for 20-30 second and repeat the stretch 2-3 times. Try some yoga. Yoga not only stretches those muscles and tendons, but can be quiet effective at building balance and strength.
Staying active will also reduce the popping and snapping. You don’t need to sit around because you’re all creaky and poppy (I think snappy is a better way to describe it-just more positive). Continuing to stay active actually increases the lubrication of your joints. So you can tell all those nay sayers who ask “Isn’t running bad for your knees?” No it’s not. As a matter of fact, it’s good for them. You can direct them to this article or just tell them to take five minutes and google it on their smart phone.
Cracking your joints or a ongoing unintentional popping of your joints won’t cause your joints to get bigger and it doesn’t cause arthritis.

Back Pain?

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Back pain is no joke. Many adults and even children suffer from back pain, specifically lower in their backs. There are a whole host of things that contribute to back pain, some are life style choices and some are genetics. Back pain can remove you from daily life activities that are both fun and necessary. Runners are not immune. Running involves repetitive stress and impact for long periods of time, which obviously has the potential to cause some back pain or tightness at some point. Maintaining good running form, following some basic training rules and keeping the back muscles loose will save you from missed work, and more importantly missed running.
Maintaining proper running form and a strength training routine (see mine here)  focusing on the core muscles (including the lower back) is going to go a long way in preventing lower back pain. Running form can make you a more or less efficient runner and it can make you a more or less injury prone runner. What is proper form? First, you don’t want to make big changes to your running form at a time, pick one of these and do it until it becomes automatic and then move to another. If you notice any pain, which you shouldn’t, make sure you are doing it correctly. If any pain continues, reduce it to every other run until it’s comfortable and then increase to every run.
  1. Head up and shoulders back, not uncomfortably but might feel a little weird if you sit at a computer for a long time each day.
  2. Chest up. Imagine a string attached to your sternum about nipple height pulling up to the sun or moon. This is probably the most helpful with aligning your body.
  3. Be aware of your legs. they should be under your body when you land not way out in front, especially downhill otherwise every step is like putting on the breaks and causes major impact to go through your body improperly.
  4. Foot plan should be mid-foot or forefoot. If you are doing one or the other, don’t switch. Basically, you don’t want to heel plant see number 3 above.
  5. Arm swing. Hold a ninety degree angle at the elbow, hands loose, like you’re holding a potato chip. Don’t cross your arms past your mid-line, center of your torso. Your elbows should come up to your hip and swing back until your wrists are at your hip. They should go straight back and then straight forward, a little pull toward the center is okay, just don’t cross over.
Another important factor, is increasing your miles by the 10% rule and taking rest weeks every 4th week (reduce your miles by 20-25% for the week). Increasing your miles too quickly doesn’t give your body enough time to build the muscle to handle the next level of training. Training with big mile jumps leads to over use injuries. Rest weeks are equally as important because they give your body time to heal and get stronger. As we run we create micro tears in our muscles. This is good because they heal stronger and build more muscle. But if you don’t give it time do do that effectively, it will just do the best it can with what it has, which doesn’t work well long term for you.
Self massage on the back. Sure being able to afford regular massages by a professional would be awesome, but not all of us runners have sponsors, which means all our money goes to our shoes and socks… That leaves massaging to our significant others or more often ourselves. The least expensive and surprisingly very helpful are La Crosse balls. Buy two of them from Amazon or a local athletic store and tape them together. Keep the tape smooth and make sure they are secure. Place the taped balls between your back and the wall with the indentation in the middle over your spine. The balls will be on either side. Now slowly raise and lower yourself against the wall. Keep your hips neutral (great squat workout too). Stop on knots for a few 20-30 seconds to see if you can get them to release. Keep going for 2 minutes or longer if you’d like.
A wonderful tool for total body massage (no they don’t pay me) is the Body Wrench, find it here. It’s a bit pricey, but remember it’s an investment in your body and it’s 100% money back guaranteed. You can use it for strength training as well (a 2-fer). It comes with a storage bag and an instruction manual. There are instructional videos online, found here.
Running forever, means we are going to do what we need to do to prevent and fix injuries and pain.

Arm Strength and Running

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This post is the first in a series of posts on what role various parts of our bodies play in running and how giving them some attention can improve our running. I’m going to work from the top to the bottom. So, what role do your arms play in running?
Your arms are important in running. Try running without them moving and you’ll find out just how important they are. Our arms propel us forward and help us maintain balance. They also catch us when we fall, hold our handheld water bottles, and make it much easier to eat and carry a hydration pack. It’s good to have arms.
Our legs move in relation to our arms. The faster we move our arms the faster our legs move. I often tell triathletes and ultraunners to focus on their arms as specific points in their races. For triathletes, it is after the transition from the bike to the run when you feel like a newborn baby giraffe.  For ultrarunners, it when you just don’t think you can take another step.
Holding our arms in the proper form is going to improve our efficiency andendurance as runners. Runners arms should be bent at about a 90 degree angle and swing pretty much straight back and forward without crossing the mid-line of your chest. Your arm should go back until your hand passes just above the hips and come forward until your elbow is close to your waist. Elbows should point backward. Your arms and hands should be held loose, but not flopping around like rubber.
If you don’t have an efficient arm swing you’re going to burn more energy than someone who does. In distance running, you want to burn as little energy with each step as you can at the speed you want to go. Too much crossover causes you to over rotate your torso. Over rotation of the torso wastes energy and can cause injuries down the kinetic chain by changing your foot plant and the alignment in your hips, knees, and ankles.
Your arms help with balance, especially, during a trail descent. Hold them out from your body and assist your core a bit to stabilize you.
Strengthening your arms will help you maintain the proper arm swing and running form throughout your run and keeps your legs moving forward when they are tired. You don’t want large arm muscles because they just add weight you have to haul around. It’s a balance. Strive for lean muscle rather than bulk. To maintain lean muscle complete more repetitions and use less weight.
The exercise shouldn’t be easy and you should feel it by the time you finish a set and the last set should be hard. If you can’t do the number of reps listed below do what you can and work up. If it’s too easy, add more reps before you add more weight.
Here are some easy things you can do to increase and maintain arm strength: push-ups 3 sets of 12-15 reps; tricep press 3 sets 10-12 reps; bicep curls 3 sets 12-15 reps; flies with arms straight and then bent 3 sets 10-12 reps.

Aerobic vs. Sport Specific Fitness

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I’m fit right? Many people who are physically fit believe they can cross over into another sport and their fitness should translate. This may be true to some extend, but if the sports are different enough, things do not translate.
There are multiple aspect of fitness that make you a strong runner (or strong any other type of athlete. Aerobic fitness is the stimulation and strengthening of the heart and lungs, which improves the bodies ability to transform oxygen you breath in to energy your muscles can use. Having enough oxygen throughout your body is critical to participating in endurance events, okay and life.
Aerobic fitness is important but it’s not enough if you want to be a strong athlete in a particular sport. Strength in the muscles specific to the sport does not always crossover and complete crossover is pretty much impossible. You can compare muscle development between athletes of different sports to see proof, unless they make special effort to achieve more balanced strength. Runners have more balanced development throughout the legs. Sometimes the calves and quads can be more developed. Cyclists typically have larger quads, specifically the one on the outside. Swimmers have larger shoulders and arms. Those who play team sports requiring a lot of lateral movement are going to have stronger supporting muscles in the legs and core.
Running uses every muscle in your body as to most other sports. The difference is in the role each plays and the level of reliance on that particular muscle group. The major muscles of the legs are the most used in running. There are smaller, support, muscles in the legs used as well. At times these support muscles are recruited to pull more of the load than normal when the big boys become fatigued or injured. Even within the running community there are going to be differences in leg development because of the training each runner does.
Muscles and tendons remember. Neuro-pathways or muscle memory develops with experience. Your body becomes more efficient in form. When you repeat a motion over and over again, it becomes ingrained and you don’t have to put much, if any, thought into it. The less you have to think about each movement the faster you will become. The reduced attention required allows you to focus on one aspect of your body and make tweaks here and there to improve your form reducing injury and energy consumption. For runners, leg turn over, cadence, and stride length are all improved by building neuro-pathways. In contrast, soccer and American football players have unmatched agility (foot movement) because they work on it day in and day out.
The range of motion required by your muscles is different for different sports and on the other side the muscles and tendons which tend to tighten up are different depending on your sport. Flexibility in the hamstrings and hip flexors is important for running because they control the movement of your leg swing. Flexibility in those muscles is not as important for swimming or rowing.
Bottom line here is don’t get frustrated when you really struggle when cross training or picking up another sport. Fitness encompasses many aspects and unless you make an effort to maintain balance across these you’re not going to be at the same level in each sport. Individual strengths also separate athletes in the same sports.