Thinking of starting your strength training plan for the summer? You may want to think about what you are using to get into shape. There are many exercise machines in the gym that you may want to avoid as they can potentially injure you if used incorrectly, even if you have a trainer. Here are 10 machines to avoid when going to the gym, and ways to use your own body to complete the exercises safely.Seated Lat PulldownIf you want to use the seated lat pulldown to train your biceps, upper back and lats, you should think of doing some incline pull-ups instead to avoid injuring your rotator cuff.Seated Hip AbductorIf you are looking to train your outer thighs, try to avoid using the seated hip abductor machine, place a looped resistance band around your legs, and try doing side steps instead. Due to the wobbliness of the seat, there can be unnecessary pressure placed on the spine.Seated Leg ExtensionTraining your quads can be done by lifting your right leg in front of you and bending your left leg. Then, squat down as far as possible with your arms straight in front of you. Use your own resistance to complete leg extensions rather than using the seated leg extension machine, as it can put strain on ligaments and tendons which surround your kneecaps.Seated Shoulder PressUsing the seated shoulder press can hurt your hips or shoulders since your hips are sedentary and restricted while moving the shoulders. The body is supposed to move together, so this machine can give you shoulder pain. Instead, throw a medicine ball at a wall about three feet away.Seated Rotation MachineTo train abs and obliques, refrain from using the seated rotation machine and instead use the cable wood chop to complete reps. The seated rotation machine puts many twisting forces on the spine that can really give back problems later.Seated Leg PressThe seated leg press has been known to force the spine to flex without use of other parts of the back or shoulders. To train quads, glutes and hamstrings, try doing some bodyweight squats instead.Smith Machine SquatsThe Smith machine is supposed to allow you to do squats with added weights. The issue with the machine is that it works linearly and does not work in natural, arched motions like your body does. Try to do some bodyweight squats instead.Roman Chair Back ExtensionIf you are looking to work the spinal erectors, try crouching on all fours and bringing your right arm together with your left leg instead of using the Roman Chair Back Extension. The machine will put pressure on your spine to the point where you could damage the discs in your back as well.Roman Chair Sit-UpTo train abs and hip flexors, avoid using the Roman Chair Sit-Up as it puts stress on the lower back. Instead do a plank.Seated Pec DeckAvoid using the Seated Pec Deck as it can make your shoulders unstable and hurt the connective tissue. Do some incline push-ups instead to train your chest and shoulders.Seated Military PressTo train shoulders and triceps, stand three feet from a wall and toss a medicine ball against it. By using the seated military Ppress, you can put stress on the shoulders by not being able to use the hips.