This one is for lauren...

Since I watched lauren struggle last night working out I decided to do some research.

Hip Joints..... Here is the research that I have found

Runner's Resource Guide: Basic Strengthening Exercises

They should be done every other day. Some of these exercises can be performed with or without weights. Do not lift weights before running. If you wish to use weights and are unable to purchase them, a hand bag with soup cans in it can be used.
Exercise both legs according to these directions. If one leg is weaker than the other, exercise the weak one only. When both legs can lift the same amount of weight, exercise both legs.

Exercise #1 - Side Lifts
Starting Position: Lie on your side on a table or firm mattress, with your body and top knee straight, and with the bottom leg bent behind your back (Fig. 1A). The top leg is to be exercised. If using weights, put the cloth or velcro strap or shortened leather belt around your instep with the weights secured. The weights should remain steady and not slide down your foot as long as you keep your foot parallel to the floor.

Action: Lift the leg slowly to a maximum height of 12 inches. Keep the leg and body straight. Do not move your hips from side to side (Fig. 1B). Hold the weight up for one second. Slowly return to starting position. Repeat 10 times; rest 30 seconds and then do another 10 repetitions. DO NOT CAUSE PAIN.

Exercise #2 - Hip Flexion
Starting position: Sit on a high desk or table with the legs hanging over the table edge at a 90 degree angle so that the weights are hanging above the floor. Grasp the front edge of the table with both hands (Fig. 2A). Secure the weights around the instep while keeping the ankle bent upwards.
Action: Keeping the knee bent, slide the thigh about eight inches off the table without taking your hands off the table (Fig. 2B). Hold for one second, then return to the starting position slowly. Repeat 25 times. Rest one minute, and then do another 25 repetitions. DO NOT LEAN BACKWARDS OR LET GO OF THE TABLE. DO NOT CAUSE PAIN IN ANY JOINT. It is normal for the muscle to feel fatigued.

Exercise #3 - Straight Leg Raises: Hip Flexors and Quadriceps
Starting position: Lie on your back on a table or firm surface. THE LEG TO BE EXERCISED IS STRAIGHT AND IN COMPLETE EXTENSION. THE OTHER LEG IS FLEXED (bent) at the hip and knee so that the foot is planted on the surface of the table (Fig. 3A). Secure the weights around the ankle to be exercised.
Action: KEEP THE LEG TO BE EXERCISED COMPLETELY STRAIGHT. SLOWLY raise the leg until the ankle is approximately 12 inches off the ground (Fig. 3B). SLOWLY lower the leg back to the starting position. Perform the exercise and repeat again 25 times, for a total of 50 repetitions.
Note:
When raising the leg, the knee must be kept STRAIGHT.

Exercise #4 - Partial Sit-Up
Starting Position: Lie on your back with the hips and knees comfortably bent (Fig. 4A).

Action: Bring the chin towards your chest and slowly lift your neck and shoulders off the floor until the back of the shoulder (scapula) is off the floor (Fig. 4B). Hold this position for one second, then slowly bring the shoulders, neck and head backward to the starting position. Relax for 5 seconds, then repeat the exercise again for a total of 10 repetitions. Increase the repetitions as you become stronger.
Note: For beginners, the hands can be placed at the side of your body to assist you. After a week or two, place your arms on your chest, and finally, after another week or two, place hands clasped behind your neck.

Click here for photo explanations

http://www.nismat.org/traintip/runner/strength.html