When it comes to improving strength through resistance training, there are many theories regarding what works best and what doesn’t work at all. Much of the information floating around the locker room is anecdotal and has very little scientific research to back it up. While you might look to a 250-pound hulk for weight training advice, odds are, what worked for him many not work for you. But what you can rely on is solid, tried-and-true evidence developed by recognized scientists in the field of health and fitness to help you improve strength in an intelligent and efficient manner, and cut down on injury potential. By making simple, challenging tweaks to your regular routine, you might just find yourself ready to audition for next season’s “American Gladiators.”

One of the most common errors weight lifters make is the use of momentum to perform an exercise. For example, in order to curl those 60-pound dumbbells, a weight lifter will throw his shoulders behind him and arch his lower back to increase the speed of movement. The problem here is two-fold. First, this type of movement can be detrimental to joints and the spinal cord by initiating unnecessary wear and tear. It also places a great deal of strain on the smaller muscles of the lower back, which can lead to chronic aches and pain. Do this and soon enough you’ll be more worried about finding a physical therapist to help you regain mobility. Second, the exerciser reduces the amount of work produced by the biceps muscle, thereby decreasing potential strength gains. Instead of focusing on the biceps, you have now involved the lower back, some muscles of the upper back, your neck and more. Subtract those muscles from the equation and it’s likely you’ll be incapable of lifting that same weight. So, to drastically improve strength of the intended muscle and to reduce injury potential, eliminate momentum from your workout. In keeping with the biceps curl theme, a great way to decrease momentum is to perform the movement with the back against the wall. With little room to maneuver, the biceps will be forced to work harder, resulting in greater gains. You may have to drop down in weight a bit, but the improvements you make will be worth a little ego bruising.

Most fitness facilities come well equipped with a variety of resistance machines. But, recent research has determined that fixed-motion machines – plate-loaded machines including the pec deck and Smith machine, which follow one plane of motion – do not elicit optimal strength gains. The study, which was published in the January issue of the Journal of Strength and Conditioning Research, finds when compared with free-motion machines (cable-based machines that allow multiple ranges of motion within the exercised joint’s capability), fixed-motion machines come up short. In fact, those utilizing free-motion machines experienced twice the strength gains during the trial period.

Study authors also found that those using free-motion machines experienced a 30 percent decrease in long-lasting joint discomfort, while their fixed-motion counterparts noted a 111 percent increase in joint pain. Further, free-motion machine users improved balance by 245 percent, while fixed-motion users only saw an improvement of 49 percent. “This study finds that the assumption in fixed training may be inaccurate,” states lead study author, Keith C. Spennewyn of the health and exercise department at the Minnesota School of Business/Global University. He believes that experienced exercisers should look to free-motion machines instead of fixed motion for greater improvements in strength. If free-motion machines are not available at your gym, a pair of dumbbells will do the trick.

Most people who go to the gym hope to develop a strong, defined midsection and spend countless hours crunching away on a yoga mat. According to researchers in the Department of Kinesiology at Occidental College in Los Angeles, you may be short-changing yourself by performing the exercise on the ground or a flat bench. Through the use of sophisticated technology, researchers set out to determine whether performing a crunch atop a stability ball was more effective than the traditional floor-based crunch. As hypothesized, subjects who used the stability ball experienced significantly increased abdominal activation over those exercising on the floor. They also found that placing the ball toward the upper back showed less activation than the floor crunch, however placing the ball underneath the lower back was far superior to both. “For those with abdominal muscle weakness, a high ball placement will allow them to perform the crunch motion with less effort than when performed on a stable bench or floor,” said the study’s lead author. Once strength gains have been achieved, the exercise can be progressed to the floor and then to the ball placed underneath the lower spine.

Those in the know may have heard of a term called periodization, which refers to a training method that requires exercisers to modify their program at varying times throughout the year. Often used by athletes, periodization is a tool that can also be effective for those looking to improve strength and limit plateaus. While various versions of this type of training abound – many of them requiring a Ph.D. in exercise science to execute – one such method can be easily adapted to your regular workout without headaches and mathematic equations.

Undulating periodization is gaining in popularity due to its relatively simple approach and impressive results. In short, the weight lifter changes the volume and intensity of resistance throughout the course of a single week. For example, if the exerciser is following a full-body workout three times per week, he would cycle through a strength training routine, an endurance routine and a muscle growth routine. On Monday, he would perform three to five sets of four to six repetitions with four to five minutes rest between sets. He might then follow with an endurance workout on Wednesday which, includes three to four sets of 15-20 repetitions with a one to two minute rest in between sets. Finally, on Friday, he would complete the cycle with a muscle-building routine that would have him performing three to four sets of eight to 12 repetitions with a two to three minute rest between sets. Ideally, the resistance would be heavy enough so that the exercised muscles were adequately fatigued toward completion of the set. Then, the following week, he would change the lineup and start with endurance on Monday, then muscle-building on Wednesday and strength on Friday. This type of programming keeps the body guessing, and limits adaptation for increases in strength, muscle size and power. Conversely, following the same routine each week can result in strength plateaus or even reversals.

The goal with strength training should always be to work smart. Following these four tips will not only help you build true strength, they will also reduce your injury potential which will keep you in the weight room working furiously toward your goals without interruption.