Old Rule: Lift weights for better bones
New Rule: Jump, too

A study from Oregon State University found women who did both lower and upper body resistance training along with jumping exercises three times a week for a year had higher bone density levels in their hips and spine compared to those who didn’t exercise. Jumping generates the quick, intense strain that bones need to become stronger. If you don’t have a history of knee injuries, fractures or a family history of osteoporosis, doing 40 to 50 vertical jumps or skipping rope for a few minutes can be one of the quickest and most effective ways to increase bone density, especially in premenopausal women.

Old Rule: Know why you need exercise
New Rule: Plan how to get it done

Adults who use behavior-oriented interventions—such as goal setting and self-monitoring—significantly increase their activity levels compared to adults who use cognitive approaches, which try to change knowledge and attitudes, according to a review published in the American Journal of Public Health. Hearing information about why you need to exercise isn’t motivating, says Vicki Conn, PhD, RN, associate dean of research and Potter-Brinton professor in the MU Sinclair School of Nursing at the University of Missouri. “We can’t ‘think’ ourselves more active.” Instead, try scheduling appointments with a personal trainer, setting exercise alerts on your phone or placing your pedometer on your work clothes the night before.

Old Rule: Warm up before exercising
New Rule: Chill out first

To perform better in the heat, cool down before you warm up. Research shows that lowering your body temperature prior to exercise increases the amount of heat your body can tolerate, which delays fatigue. The best way: Slowly sip a flavored ice slushie starting 30 minutes before you exercise. Athletes who did this before running on a treadmill in hot room ran an average of 10 minutes longer than those who drank cold, flavored water, according to a 2010 study in the journal Medicine & Science in Sports & Exercise. Because the runners’ bodies had to convert the slushies from ice to water, they may have transferred more heat to the drink rather than store it internally where it would have raised their core temperatures, say researchers.

Old Rule: Avoid exercising in heat
New Rule: Allow your body to acclimate

If you want to boost your cold-weather performance, train in hot weather: Cyclists who rode spin bikes in a lab heated to 104 degrees they were able to ride four to eight percent faster in a cooler room at the end of the study than cyclists who trained in the cold all along, according to a University of Oregon study. Adapting to heat allows the body to sweat earlier and heavier and expedites blood flow to the skin, all of which can positively affect performance, say researchers. Just be sure to start slow: Researchers recommend gradually increasing the time and intensity of hot workouts over multiple sessions in the sun.

Old Rule: Build strength with heavy weights

New Rule: Lighten up

In a 2010 study, McMaster University researchers found that lifting lighter weights results in a 25 percent greater rate of muscle protein synthesis, which is essential to building muscle, than hoisting heavy loads as long as you do repetitions until fatigue. “We call this the high-effort routine,” says study author Stuart Phillips, PhD, associate chair of graduate studies at McMaster University. It also burns more calories. To incorporate this type of training, choose a weight that is about 30 percent lighter than the most you could lift and perform the exercise until fatigue. For most people, that entails at least 24 reps.

Old Rule: Run hard to get faster
New Rule: Slow down

Stuck at your current speed? You may be training too hard, posits a study published in the Journal of Strength and Conditioning. According to the researchers, spending too much time doing tempo runs just above your lactate threshold—a moderate-intensity pace at which the body starts producing lactic acid—can have detrimental effects on performance. To test their theory, the researchers divided well-trained runners into two groups. One did 25 percent of their training at this moderate intensity. The other only did 12 percent of their runs at this effort level and used the time saved to do more low-intensity running. After five months the latter group improved their 6.5-mile race time by an average of 36 seconds more than the former group. It’s possible that doing too much moderate-intensity running places more stress on the body than it can adequately recover from. “If the runner can dedicate more time to daily training sessions, it seems better to design an ‘easy-hard’ distribution load (increasing the amount of low-intensity training), than a ‘moderate high-hard’ training approach,” says study author Jonathan Esteve-Lanao, an exercise physiologist at the European University of Madrid in Spain.

To avoid short changing yourself, devote 80 percent of your training to low-intensity running, 12 percent to moderate-intensity (ie: a heart rate that’s 75 to 80 percent of your max) and 8 percent to high-intensity work, such as sprints. Calculate your max heart rate using this women’s-specific formula: 206 - (0.88 x age).

Old Rule: Gradually lift more weight
New Rule: Adjust expectations day by day

Linear periodization (LP)—in which you increase how much weight you lift in pre-set increments—may not be the best way to built strength. When researchers had a group of athletes use this approach and autoregulatory progressive resistance exercise (ARPRE)—in which you adjust how much you’re lifting according to how you feel and how you’re perfoming—they found that athletes training by the ARPRE approach increased their max squat by 193 pounds, compared to 37 pounds in the LP group and their max bench press by 93 pounds compared to virtually no change in the LP group, according to a six-week study published in The Journal of Strength and Conditioning. The constant adjustment of repetition that is characteristic of LP may prevent the body from adapting to the training, says study author J. Bryan Mann, MEd. To implement ARPRE in your own training, adjust your routine based on how you feel and are performing on that day. For instance, if the weight you’re hoisting feels too heavy (despite the fact that it felt easy last week), grab a smaller dumbbell. If it feels too easy, go up a few pounds.

Old Rule: Eat breakfast before you exercise
New Rule: Postpone your morning meal

If you’re trying to lose weight, do cardio before your morning meal, suggests a new study published in The Journal of Physiology. Researchers put a group of healthy, active adults on a hyper-caloric, high-fat diet and then assigned them to one of three experimental groups. The first did no exercise. The second and third groups did identical, strenuous, 60- and 90-minute running and cycling workouts four times a week but followed different dietary protocols around the time of training: The second group ate a carbohydrate heavy breakfast an hour and a half before exercising and then continued to take in carbs during their workout with a sports drink-like mixture, while the third group exercised on an empty stomach, drank only water during the workout and then ate the carb-rich breakfast mid-afternoon.

After six weeks the non-exercisers gained about six pounds and developed insulin resistance, an early sign of type 2 diabetes, and began storing fat in their muscles. The pre-exercise breakfast eaters gained about half as much weight but also became more insulin resistant and started to store more fat. Only the group that exercised before breakfast gained virtually no weight and burned the extra fat they were eating more efficiently. Exercising in a fasted state may cause metabolic changes in muscle that causes them to burn fat, instead of carbs, for fuel, say researchers.

If you want to try exercising on an empty stomach but are worried your performance will suffer, there is good evidence that swishing—but not swallowing—a carbohydrate solution, such as Gatorade, can significantly enhance performance in the fasted state, says study author Peter Hespel, PhD, professor in the Research Center for Exercise and Health at Catholic University Leuven in Belgium. "A simple mouth rinse just before starting the exercise certainly would delay the perception of fatigue during the exercise, and thus enhance the ‘quality’ of the training."

Next: 10 Summer Workout Mistakes That Stall Results

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