Not Enough Fluid
We’ve all heard it many times, “Hydrate, hydrate, hydrate.” Especailly in warm weather, the body can dehydrate quickly. With even 1-2% of the body weight lost as sweat, performance will suffer. Training should include hydration so that you will be able to drink during the event. Practice keeping up with your fluid losses, especially for an event that lasts more than 1 hour. How much should you drink? That depends upon how much you are losing. Weigh yourself before and after a 30 minute training session. The weight you lost equals how much fluid you lose every 30 minutes (one pound equals 16 fluid ounces)
Too Much Fluid
When you become too focused on hydration, it is possible to drink too much. Excess fluid will cause you to dilute the electrolytes in your body, possibly causing confusion, cramping and even seizures.
Not enough carbohydrate
When you combine endurance training with calorie restriction, you create a recipe for disaster. Prolonged endurance workouts require calories from carbohydrates to keep the muscles fueled to work adequately. If you don’t eat before a long or intense workout, you set yourself up for muscle fatigue and perhaps injury. If you cramp after eating, consider taking liquid “meals” before training. Cool, dilute (5 grams of carbohydrate in every 100ml) liquids
Not enough intensity
Endurance event training relies not only on your slow twitch (Type 1) muscle fibers, but also on your fast twitch (type 2) fibers to provide you with power. Training at an intensity below which the type 2 fibers are used will leave you out of breath when you hit a hill or when you try to pick up the pace.
Training today will take about six weeks to see an increase in fitness. Training hard in the week before an important event will only maintain fitness, not improve your fitness for race day. Over the last week to 10 days prior to an important event, decrease the amount of time you spend training by half while keeping your intensity the same.
Doing what the other guy did
One of the biggest problems with training for any sport is following the training plan of a friend or professional racer. Every person has a different muscle fiber profile and will respond differently to the same plan. To truly understand what will work for you, a number of variables need to be taken into account—most of which are only determined through exercise testing.
Too much too soon
If you have never tried a particular food before, you wouldn’t stuff your mouth the first time you tried it. The same is true with training: take a taste before you sit down for a full meal. Start out slowly and progress. Make sure that your shoes are comfortable, that your sunglasses fit, you aren’t developing any injuries and any chafing is addressed before continuing to add miles.
Improper footwear selection
The foot has two arches, one that runs the length of the foot and one that runs across the foot. Different feet need different support for these arches, some feet even need orthotics whether over the counter or custom. Be sure your footwear selection matches your feet before undertaking large volume training. A good running store, sports medicine physician or biomechanist can help find a shoe that is right for you.
Running Through Pain
Ignoring aches and pains and letting them progress to chronic overuse injuries is common. If you want to be pain free and complete your goals, don’t ignore pains while they are still easily treated.
Forgetting the rest of the body (core)
Although marathon training should involve lots of running, it should also involve core training. The core, defined as the muscles that stabilize the trunk so that the arms and legs can do their thing, plays a very important role in increasing speed and limiting injuries. The hip stabilizer muscles in the butt can be strengthened with side planks and lunges. Training should be functional and based upon weight-bearing exercises (sitting in a thigh-toning machine won’t necessarily help for running).