Effectiveness of Different Kinds of Strength Training Periodization

Periodization of strength training entails changing over time the weight handled in each exercise along with the number of repetitions per set. When the weight used is higher, the number of repetitions is lower and when the weight used is lower, the number of repetitions is higher. It is widely agreed among strength and conditioning professionals that periodized strength training is more effective than non-periodized training.

There are various versions of strength training periodization, including:

• Traditional periodization - The trainee starts with relative light weights and high repetitions, and over a period of several weeks, increases the amount of weight lifted while decreasing the number of repetitions. For example, the trainee might begin by doing 10 repetitions per set with 60% of the maximum weight that can be lifted for a single repetition and progress to 4 repetitions with 80% of the max weight.
• Daily Undulating Periodization - On different days, the trainee uses a different combination of weights and repetitions. A sample schedule might be medium weight and medium reps on Monday, light weight and high reps on Wednesday, and heavy weight and low reps on Friday.
• Weekly Undulating Periodization - Weight and reps fluctuate from week to week. A sample schedule might be low weight and high reps on week 1, medium weight and medium reps on week 2, and high weight and low reps on week 3, with this 3-week pattern repeating several times.

A recent study by Apel, Lacey, and Kell in the Journal of Strength and Conditioning Research (vol. 25, no. 3, pp. 694-703, 2011) sought to determine the relative effectiveness of traditional vs. weekly undulating periodization.

Experimental Procedure
Forty-two young, physically active men were divided into three groups of 14 that trained for 12 weeks as follows:

• Control group - Performed no strength training
• Traditional periodization (TP) - Increased the resistance in a fairly linear manner from 57% of max the first week to 80% of max the final week.
• Weekly Undulating Periodization (WUP) - Started at 57% of max, but increased resistance over 3 weeks before reducing weight close to where it started and increasing it back again over 3 weeks. This was done over 3 cycles in which both the starting and ending weight for each 3-week cycle became greater than for the previous 3-week cycle, ending at 78% of max.

There were 15 different exercises selected to work the entire body. The exercises used, rest time, total exercise volume and average percent of maximum weight used were the same in both groups. There were 3 training sessions per week for the first 2 weeks and 4 per week for the remaining weeks, in which half the exercises were performed 2 days per week (e.g. Mon. and Thu.) and the other half on 2 other days per week (e.g. Tue. and Fri).

Results

• Both periodized training groups increased significantly in strength, while the control group did not.
• Increases in back squat strength were significantly greater for the TP group (54%) than for the WUP group (34%).
• Increases in bench press strength were significantly greater for the TP group (24%) than for the WUP group (19%).
• Increases in pull-down strength were significantly greater for the TP group (29%) than for the WUP group (19%).
• Increases in dumbbell shoulder press strength were significantly greater for the TP group (48%) than for the WUP group (36%).
• Increases in leg extension strength were greater for the TP group (39%) than for the WUP group (27%), although the between-group difference did not reach statistical significance.
• There was more muscle soreness and fatigue reported among the WUD group, which may have hindered training progress.

Bottom Line
For this group of recreationally active males, traditional periodization produced superior results to weekly undulating periodization. The between-group differences were great enough to be meaningful.

Maintaining Strength and Muscle Mass As We Age

An article entitled, “Staying Strong: How exercise and diet can help preserve your muscles” appeared in the April 2011 issue of the Nutrition Action Health Letter, a publication of the Center for Science in the Public Interest. The article stated some interesting facts, including:

• Starting in their late 30s and early 40s, most people lose a quarter pound of muscle per year.
• Several studies have shown that resistance exercise can restore and preserve strength and power, even at an advanced age.
• Resistance exercise also helps prevent loss in bone density and may even reverse age-related loss.
• People with Type II diabetes can lower their blood sugar by doing resistance exercise.
• After a large protein feeding (~ 30 grams, the quantity in 4 ounces of cooked meat) both younger and older people show equivalent protein synthesis (muscle-building) responses.
• After a small protein feeding (~ 14 grams, the quantity in an egg plus a glass of  milk) younger people synthesize about half the protein they synthesized in the large feeding BUT PEOPLE OVER 60 SHOW ALMOST NO PROTEIN SYSTHESIS. In other words, the larger protein portions are necessary for the older people to synthesize any protein at all. However, anything above 30 grams of protein in a meal is either burned off as energy or stored as fat. So extremely large protein meals do not aid in muscle-building.
• Of the 9 essential amino acids that our bodies can’t manufacture and must ingest, leucine is by far the most important for muscle development, especially for older individuals. Researchers recommend a minimum of 3 grams of leucine per meal, in addition to other amino acids. Animal products generally have relatively high percentages of leucine. Protein from whey (a byproduct of cheese-making) is relatively high in leucine and makes a good protein supplement.
• Plant protein contains a smaller percentage of leucine, but soy is the best of the common plant proteins in regard to leucine content.
• According to researchers, ingesting protein shortly after exercise provides the greatest boost for muscle building. Two hours is the longest one should wait before ingesting protein after resistance exercise.
• While the U.S. Institute of Medicine set a Recommended Daily Allowance (RDA) of 0.36 grams of protein per pound bodyweight per day, researchers feel that about 0.50 grams of protein per pound bodyweight per day can best promote muscle building and minimize muscle loss as we age.

Bottom Line
Regular resistance exercise and adequate protein intake are essential for increasing and maintaining strength and muscle mass, especially as we age. A daily protein intake of half a gram per pound bodyweight is recommended (e.g. a 200 lb person should take in 100 grams of protein daily). The protein should not be concentrated in one meal but should be distributed over the day in meals containing about 30 grams of protein.

13 Iowa Football Players with Rhabdomyolysis: A Case of Coaching Incompetence

Thirteen University of Iowa football players were recently hospitalized for rhabdomyolysis caused by extreme physical exertion. Symptoms of the ailment include dark-colored urine, fatigue, muscle weakness, and muscle tenderness. Although the athletes have since been released from the hospital, information has not been released as to whether any permanent injury has resulted.

Rhabdomyolysis is a serious medical problem. It occurs when myoglobin leaks out of muscle cells due alcoholism, crush injuries, heatstroke, extreme physical exertion and other causes. Just as hemoglobin in red blood cells carries oxygen to the muscles and other body tissue to provide energy through oxidation of carbohydrates and fats, myoglobin carries oxygen within the muscle cells to the mitochondria, which are the oxidative energy-production units within the cells. Myoglobin is a large molecule and, when it leaks into the blood stream, it travels to the kidneys for removal. However, the myoglobin molecules are too large for the kidneys to readily clear, and can easily block the kidney’s filtration system. In addition, myoglobin breaks down into potentially harmful compounds. Permanent kidney damage or even kidney failure may result, which may require lifelong dialysis or a kidney transplant. See the National Institutes of Health for further information on rhabdomyolysis.

Extreme muscle soreness brings with it with a significant risk for rhabdomyolysis. Virtually all muscle soreness is attributable to the eccentric phase of exercise, which occurs when the muscle is lengthened while resisting. This occurs in the lowering phase of every weightlifting or calisthenic repetition, and also in the initial ground-contact phase of running, particularly downhill running. It also occurs during the deceleration phase of sports activities, as in braking for directional change and bringing a moving limb to a halt.

There is no excuse for any strength and conditioning coach to induce rhabdomyolysis. The press has reported that the workouts of the Iowa football players were extremely severe and may have been used as a punishment. One athlete said, “I had to squat 240 pounds 100 times and it was timed. I can’t walk and I fell down the stairs.” Another one said, “Hands Down the hardest workout I’ve ever had in my life!”. In addition, the severe workout occurred just after the athletes returned from winter break, during which most of them had not engaged in heavy resistance exercise. That made them particularly vulnerable to extreme muscle soreness and rhabdomyolysis.

Such an approach is totally unnecessary. Firstly, exercise should never be used as a punishment. Secondly, any knowledgeable and competent coach has to be aware that any exercise regimen that induces extreme muscle soreness presents a significant risk for rhabdomyolysis. Muscle soreness is not a prerequisite for muscle strengthening! The most effective way to increase strength is to start with light resistance and gradually increase the weight lifted over a period of time as the muscles strengthen. High repetitions are totally unnecessary for strength and power athletes like football players. Muscle fatigue following a workout is expected and desirable within limits, but muscle soreness is unnecessary and can actually slow down progress in strength development.

An extensive article and interview of coaches, doctors, and a parent of one of the players is available on the Internet.

Does Heavily Advertised Exercise Equipment Really Provide Advantages?

Advertisements on TV and elsewhere make it appear that, if you buy the latest innovative exercise device you will make faster and greater gains than you could using more conventional exercise equipment. Unfortunately, such claims, however seductive, do not usually stand up to scrutiny. The following articles in the December 2010 issue (vol. 24, no. 12) of the Journal of Strength and Conditioning Research highlight instances in which such equipment fails to provide any training advantage over standard exercises.

An article by Youdas et al. (pp. 3552-3562) compared the electrical activity of 4 chest, arm, and shoulder muscles of 20 subjects doing pushups using the Perfect-Pushup device and the same subjects doing standard pushups. The Perfect-Pushup device allows free horizontal rotation of the hands during the pushup movement while, during the standard pushup, the hands maintain their position throughout the movement. Pushups both with and without the device were done 3 different ways - using wide, shoulder-width, and narrow hand placements. While the results showed some small advantages of either the Perfect-Pushup or standard pushup as to the intensity of involvement of specific muscles when using particular hand positions, neither the Perfect-Pushup nor standard pushup showed any overall superiority to the other form of exercise. Hand position had a much more striking effect on muscle involvement, indicating that pushups should be done at various hand placements in order to stimulate a wide range of chest, shoulder, and arm musculature.

Another article by Youdas et al. (pp. 3404-3414) compared exercise using the Perfect-Pullup device to standard pull-ups (overhand grip) and chin-ups (underhand grip) using an overhead straight bar. The Perfect-Pullup device allows free horizontal rotation of the hands during the pull-up movement while, during the standard pull-up and chin-up, the hands maintain their position throughout the movement. Muscle electrical activity sensors were used to monitor the effort of 7 different muscle groups for 21 men and 4 women during the exercises. The results showed that, while there were some significant differences in muscle activation between the chin-up and pull-up, there were no significant differences between the Perfect-Pullup device and either the chin-up or pull-up. The authors concluded that the Perfect-Pullup device did not provide any advantage over standard pull-ups or chin-ups.

An article by Willardson et al. (pp. 3415-3421) compared the electrical activity of 3 abdominal muscles and 1 set of back muscles during 3 traditional trunk exercises and abdominal exercise using a device called the Ab Circle. Results showed no statistically significant differences in muscle activity between the Ab Circle and standard exercises. Yet the mean activity of the rectus abdominis muscles (6-pack) and lower abdominal stabilizer muscles was highest during the standard crunch, and the erector spinae (low back) muscles and external obliques (lateral waist) were most active during the side bridge. Thus the Ab Circle provided no advantage over standard calisthenic exercises for working the abdominal and low back musculature.

An article by Schoffstall, Titcomb, and Kilbourne (pp. 3422-3426) compared the electrical activity of 5 muscles involved in abdominal and hip flexion (upper rectus abdominis, lower rectus abdominis, internal obliques, external obliques, and rectus femoris) during the following isometric exercises:
- Crunch
- Supine V-up (while facing upward, back and legs rise off the ground to make a V-shape)
- Prone V-up (while facing down, butt rises up while hands and feet approach each other, making inverted V-shape) done as follows:

• Feet on ground (no equipment)
• Feet on FB large exercise ball
• Feet on Power Slide
• Feet supported by TRX suspension straps
• Feet on Power Wheel

The results showed that:

• All exercises stimulated the external obliques, upper rectus abdominis, and lower rectus abdominis similarly
• The supine V-up without equipment showed greater internal oblique activity than the V-up done on the slide board.
• The rectus femoris was less active during the crunch than during any of the other exercises. This is not surprising since the knees are specifically bent during a crunch to take the hip-flexors out of play and focus only on the abdominal muscles.
• Overall, the prone and supine V-up exercises done without equipment provided as much training stimulus to the muscles tested as did the prone V-up using any of the commercial equipment.

Bottom Line
These studies indicate that much of the exercise equipment heavily marketed to the public provides no advantage in training stimulus over standard exercises. The only advantage of such equipment is that it provides variety, which may be important to maintain the motivation to exercise. Some exercise enthusiasts, even when informed that such equipment usually provides no shortcuts to the results they desire, may still wish to purchase them in order to keep their workout fresh, and that is fine. However, for those who would rather use their money for different purposes, there are other ways to add variety to a workout. Using standard gym equipment, a wide variety of exercises can be performed, especially using free-weight barbells and dumbbells and an overhead bar for hanging exercises.

Plyometric Training for Improved Sports Performance

Plyometric training has been popular among strength and physical conditioning coaches for a number of years. Yet many people who exercise on their own are not familiar with this method. Simply put, plyometric exercise involved rapid stretch and shortening of a muscle. This occurs in such movements as hopping, jumping, and bouncing. For example, when you jump vertically, you naturally first do a countermovement in which you bend your knees quickly while stretching your quadriceps (front thigh) muscles, then rapidly contract those muscles to straighten the knees and propel the body upwards. Thus, repeated vertical jumps are one kind of plyometric exercise.

There are various gradations of plyometric exercise, and it is considered prudent to start with low-stress ones before progressing to more difficult ones. One of the most stressful plyometric exercises is depth-jumping, in which one jumps down from a box and, after contacting the ground, immediately jumps vertically. This is considered dangerous for anyone who does not already have a strong lower body and has not progressed from low-stress, through moderate-stress, to high-stress plyometric exercise. Various sources have recommended being able to squat with 1.5 times one’s bodyweight before taking on a serious plyometric exercise program. However, it is generally considered safe for people in good health without orthopedic problems to perform low-stress plyometric exercises like low bounces, hops, and jumps.

A recent study by Chelly et al. in the Journal of Strength and Conditioning Research (Vol 24, no. 10, pp. 2670-2676, 2010), showed how effective plyometric training can be.

Method
A group of experienced young male soccer players, average age 19 years, trained as follows:

• August - preseason training consisting of light resistance exercise and calisthenics
• September through March (the competitive season) - The players trained 5 days per week for 90 minutes by doing skill and tactical drills along with 30 minutes of continuous play. On one day per week they engaged in a competitive soccer game against another team.

The subjects were divided into 2 groups:

Group 1 only did the training program above.
Group 2 did the training program above plus from January-March they also did the following plyometric training twice per week:

• Week 1: 5 sets of jumping over ten 40-cm (24“) hurdles spaced 1 meter (39.4”) apart
• Week 2: 7 sets of jumping over ten 40-cm (24“) hurdles spaced 1 meter (39.4”) apart
• Week 3: 10 sets of jumping over ten 40-cm (24“) hurdles spaced 1 meter (39.4”) apart
• Week 4: 5 sets of jumping over ten 60-cm (36“) hurdles spaced 1 meter (39.4”) apart
• Week 5: 4 sets of depth-jumps from a 40-cm (24“) box
• Week 6: 4 sets of depth-jumps from a 40-cm (24“) box
• Week 7: 4 sets of depth-jumps from a 40-cm (24“) box
• Week 8: 4 sets of depth-jumps from a 40-cm (24“) box

Extensive testing on speed, power, and jump height was performed before and after the training.

Results

The group that did regular soccer training did not show significant improvement in any of the pre-post tests.

The group that did plyometric training in addition to their regular soccer training showed the following statistically significant improvements:

• Thigh muscle volume: +2.5%
• Cycle ergometer absolute power: +4.5%
• Cycle ergometer power relative to body mass: +5.9%
• Jump height without a countermovement: +8.3%
• Jump height with a countermovement: +2.5%
• 40-meter sprint first step velocity: +18.2%
• 40-meter sprint velocity over first 5 meters: +10.0%
• 40-meter sprint velocity between 35 and 40 meters: +9.8%

Bottom Line
Although not all studies of plyometric training have produced improvements of this magnitude, it appears that the evidence supports inclusion of plyometric exercise in physical training programs for sports involving sprinting and/or jumping.

NOTE: This description of experimental results is for informational purposes only and does not constitute a recommendation. Anyone engaging in an exercise program should obtain proper medical authorization before doing so.

Static Stretching Can Impair Distance Running Performance

At times it can be difficult to find sports science articles that have true relevance to athletes. But here's one that can have real impact. A study by Wilson et al. (Journal of Strength and Conditioning Research, vol 24, no. 9, pp. 2274-2279, 2010) provides strong evidence that static stretching before a distance-running event can impair performance among young, male athletes.

Static stretching involves stretching a muscle to the point of mild discomfort and holding the stretch for 10-30 seconds. We have previously highlighted previous evidence that static stretching can impair jumping performance. It has also been shown to reduce maximal leg-press strength, 20-meter sprint speed, and knee-extension torque. Yet this is the first study to examine the effect of static stretching on endurance performance.

Experimental Procedure
10 male collegiate competitive distance-runners and triathletes who ran at least 20 miles per week and were in excellent aerobic condition were tested on 2 different days, at least a week apart, after the following:

1. 16 minutes of stretching consisting of the following 5 stretches each performed 4 times for 30 seconds of holding:: 1) sit on floor with knees straight and reach with both hands to and beyond the toes, 2) stand with balls of feet on a block, letting bodyweight stretch calves, 3) for both left and right, stand on 1 leg and pull the opposite heel toward the butt 4) for both left and right, lunge deeply, and 5) cross the left leg over the right one, and pull the right thigh towards the torso, repeating for other side
2. Quiet Sitting

After stretching or not stretching, the subjects underwent the following treadmill tests:

1. Run at 65% of maximal aerobic capacity (VO2max) for 30 minutes while energy-cost is measured.
2. After 2 minutes of rest and rehydration, run as far as possible in 30 minutes (subjects could control treadmill speed and see a time display, but not see a speed or distance display).

Experimental Results
On the no-strech day, the athletes performed significantly better as follows:

• They covered an average of 6.0 km in 30 minutes on the no-stretch day compared to 5.8 km on the stretch day
• They required an average of 425 calories on the stretch day vs. 405 calories on the no-stretch day to do the 30-minute submaximal run.

Bottom Line
Static stretching before running hurt the athletes' distance-running performance. After stretching they required more energy to run the same speed in the submaximal test, while in the maximal-distance 30-minute test they were not able to run as far. These differences can easily affect the chance of winning a race. The negative effect of static stretching appears to be due to a reduction in the spring-like stiffness of the leg muscles resulting in lower efficiency. Thus, it does not appear advisable to do static stretching before distance-running events. While dynamic stretching has not been subject to similar testing, it is a possible alternative. The evidence suggests that the best warmup before a distance-running event may be walking followed by jogging followed by short-distance runs at speeds increasing to race-pace.

Can Mental Imagery Improve Physical Strength?

Mental imagery involves envisioning oneself performing a physical activity without actually doing it. It is currently used by many high-level athletes to enhance their physical performance. While the method is well-accepted for maintaining focus and consistency of technique, its use has recently been examined for improving strength as well.

Study Method
In a study by Lebon, Collet and Guillot in the Journal of Strength and Conditioning Research (vol. 26, no. 6, pp. 1680-1687, 2010) male college athletes who had not been weight training were put on a program of bench-press and leg-press training 3 times per week for 4 weeks. The only difference between the training groups was that the imagery group visualized doing each exercise during the between-set rest periods while the control group performed another thought task.

Results
Both groups improved in strength and the number of repetitions they could perform with 80% of the maximal weight they could lift during pre-training tests. However, the imagery group improved 26% in leg press strength vs. 21% in the control group. Repetitions with 80% of pre-training max increased 92% in the imagery group vs. 79% in the control group. Both between-group differences were statistically significant. There were no differences between training groups as to changes in bench-press performance and neither group showed any significant increases in muscle-size.

Bottom Line
It is known that the strength gains resulting from the first few weeks of training are largely due to neuromuscular adaptations rather than muscle-size increases. Mental imagery may enhance the neuromuscular component of strength change and thus the most applicable to novice lifters. It is not clear why the method was effective for the leg press but not the bench press.

Should You Skip Breakfast to Burn More Fat During a Workout?

An Associated Press article suggesting that, because skipping breakfast before a workout burns more fat, such a practice may be effective for body fat loss. Yet, the study on which the article is based provides absolutely no evidence that such a practice would result in a stable loss of body fat. Sure, if your body is depleted of stored carbohydrates in the form of muscle and liver glycogen, you will burn more fat during exercise. However, a close look at the article reveals that the fat burned is in the muscle, and not around the waist or other parts of the body where people generally want to lose fat. Thus, exercising in a fasted state merely depletes intramuscular fat that is replenished upon eating. So there is no net body fat loss unless one consumes fewer calories than are used, which requires dietary control. So we can’t escape from the truism that the only way to lose weight is to burn more calories than you take in.

The following are additional reasons not to exercise in a fasted state:

• You will feel less energetic and more lethargic
• The quality of your workout will diminish
• Your motivation to exercise will be reduced
• You will cannibalize muscle to convert protein into needed carbohydrates

The only advantage to running in a fasted state might be for long-distance runners who wish to train their bodies to preferentially burn fat, thereby sparing muscle and liver glycogen to avoid “hitting the wall” late in a race. However, training with long-distance runs accomplish the same goal.

Caffeine May Interfere With Muscle Building

An online article in the Journal of Sports Science and Medicine by Wu and Lin (vol 9, pp 262-269, 2010) indicates that going heavy on the caffeine before resistance training may be counterproductive.


Experimental method
Ten men performed a workout consisting of 3 sets of 8 exercises. Each set consisted of 10 repetitions of 75% of the weight that could be lifted only once. On one day, the workout was performed an hour after caffeine ingestion and on another day an hour after ingesting a non-caffeinated placebo. The amount of caffeine was 6 mg/kg or about 475 mg for a 175 lb man. That’s about the amount of caffeine in one-and-a-half 16 oz Starbucks Grande coffees or four-and-a-half 8 oz cups of home-brewed coffee. Blood was analyzed at various times for levels of insulin, testosterone, cortisol, growth hormone, glucose, free fatty acid and lactic acid.

Results
As has been observed in previous studies, blood levels of free fatty acids were higher in those who ingested caffeine than in those who did not. That is why caffeine is considered an ergogenic aid (performance enhancer) for endurance sports. Long distance runners often take in caffeine to promote the burning of fats in preference to carbohydrates, allowing the limited store of carbohydrates in the muscle and liver to last longer, sparing the athlete from “hitting the wall’ later in the race.

A result not noted in previous studies was that blood concentration of human growth hormone (HGH) was significantly lower when the subjects had previously ingested caffeine than when they hadn‘t. Since HGH is a muscle-building hormone, caffeine ingestion prior to resistance training can be considered counterproductive.

There were no significant differences in blood levels of insulin, testosterone and cortisol between caffeine and no-caffeine conditions.

Bottom Line
It appears prudent to avoid caffeine consumption for at least 3 hours prior to a resistance training session in order to maximize results. Since the time it take for the body to rid itself of half of ingested caffeine is approximately 5 hours in healthy adults, then excessive caffeine consumption is not recommended, even several hours before a workout.