Slowly jog half of a mile before stretching. Doing so allows you to warm up your joints and muscles before you stretch them, thus preventing injury. Be sure to perform dynamic stretches that include motion such as: Leg lifts. Swing one leg out to the side as far as you can swing it, and then swing it back across your body in front of your standing leg, as far as possible. Repeat this stretch ten times on each leg. Cheerleader Kicks. Keep your back and knees straight, and walking forward, lift your legs straight out in front in an exaggerated march, and flex your toes towards you. Butt kicks. Perform an exaggerated running-in-place motion while standing to loosen up your knees, hamstrings, and quads. Walking lunges. Squat into a wide lunge with one foot dramatically out in front of the other, and continue to switch between legs as you slowly progress forward. Shoulder stretches. Don't forget to stretch your torso and shoulders to prevent cramping during your run. You use your arms to propel you forward when you sprint, so you'll need to be loose and limber. Pull one arm straight across your chest and hug it in with the forearm of your other arm. Switch sides and stretch the other arm. Use a stopwatch to log yourself for various mileages in order to track your progress. Incorporate hills into your runs two to three times per week to push your boundaries and condition your body. Try following this example weekly routine: Day 1: 10-20-10. Jog for 10 minutes, run briskly for 20 minutes (80% effort), and then jog for another 10 minutes. Day 2: Sprint training. Head to a track and practice sprints. Jog 12 mile (0.8km), then run another mile, sprinting the straightaways and jogging the turns. Start out with just the mile and a half, and gradually increase your distance. Day 3: Rest. Day 4: Long 60-90 minute run. Run at a pace that is comfortable enough to keep going. Day 5: 10-20-10. Jog for 10 minutes, run briskly for 20 minutes (80% effort), and then jog for another 10 minutes. Day 6: Rest. Day 7: Sprint training. Head to a track and practice sprints. Jog 12 mile (0.8km), then run another mile, sprinting the straightaways and jogging the turns. Start out with just the mile and a half, and gradually increase your distance. Being patient with yourself is one of the most important aspects of building endurance. Avoid pushing yourself to run too far until you have become comfortable with a gradual distance increase. Basically, don't try to run six miles right off the bat. Start out with one mile, then build up to a mile and a half, then two miles, etc. Don't try to sprint out a five-mile run, you'll exhaust (and maybe even injure) yourself. Start off with a light jog and gradually build up your speed as you run. Your breath can have a huge impact on your ability to run long distances. Make sure you are breathing in and out of your nose, or in through your nose and out through your mouth, depending on your preference. A steady breath means a steady heart rate and a higher lung capacity.

Summary: Warm up and stretch. Time yourself to set your baseline. Put yourself on a regiment that builds endurance and speed. Increase your distance gradually. Pace yourself. Pay attention to your breathing patterns.

A genotype is the heritable, genetic code of an individual. An individual's genotype comes from the alleles on the two chromosomes inherited from their parent. An allele is the specific form of a gene. For example, a gene codes for hair color but one allele could code for blonde hair, while another codes for brown hair. Every individual has two chromosomes with two alleles that make their genotype so it is represented with two letters. Capital letters indicate dominant alleles while lowercase letters represent recessive alleles. It doesn't matter what letter you choose to represent your gene of interest, so choose something that makes sense to you. Usually, the first letter of the dominant allele is used. For example, B represents the dominant gene for brown hair and b represents the recessive gene for blonde hair. As its name suggests a Punnett square is just a divided square. Draw your square and divide it into four smaller squares by drawing two lines (one horizontal and one vertical) through the center of the square. Leave enough room in each box for two letters. Also, leave room at the top and left side of the square. For example, let's say the mother has brown hair and a genotype of Bb, then you would put a B over the top left-hand square and a b over the top right-hand square. It doesn't matter where you put each parent's genotype. Only one letter goes above each column. For example, if the father also has brown hair, but his genotype is BB, you would put one B to the left of the upper left-hand square, and another B to the left of the lower left-hand square.
Summary: Understand genes and genotypes. Draw a 2 x 2 grid. Label the top of the square with one parent genotype. Label the left side of the square with the other parent genotype.