New Army Physical Fitness Test to Simulate Battlefield Activities

On February 28, 2011 the Official U.S. Army website reported that, after 30 years of using the same physical fitness test, the Army is developing a new physical fitness test battery to better simulate battlefield activities. The previous test was comprised of the following 3 tests done with a short rest in between:

• As many pushups as possible in 2 minutes
• As many situps as possible in 2 minutes
• Running 2 miles a quickly as possible

Scoring was based on age and gender. See our web site for testing details and scoring charts.
The revised test has not been finalized, but trials are being held this month on 7 Army bases and at the U.S. Military Academy at West Point. A review and approval process will take place before full implementation. The article states that there will be a general physical readiness test for all soldiers and a physical readiness test for those going into combat:

Army Physical Readiness Test

• 60-yard shuttle run
• one-minute rower (see diagram)
• standing long-jump
• one-minute push-up
• 1.5 mile run

Army Physical Readiness Test
The examinee will be timed while performing the following obstacle-course sequence while wearing a combat uniform and helmet and carrying a rifle:

• 400-meter run
• Low hurdles
• high crawl
• Over and under
• casualty drag
• Balance beam while holding ammo cans
• Point and move
• 100 yard shuttle sprint while holding ammo cans
• Agility sprint around cones

See the Army article for a diagram of the course. As with the current Army Physical Fitness Test, scoring charts will be developed that take age and gender into consideration.

The change in the fitness tests appears to be a good one because the new test more closely simulates battlefield physical demands. It might even be better if the Physical Readiness Test were performed while the examinees carried a combat load similar to those normally worn by soldiers.

Mens-fitness-and-health.com is very supportive of functional training that seeks to improve performance in sports, combat, or daily living. Function-based training programs emphasize improved physical performance rather than appearance. Workouts designed to “get big” generally train isolated muscle groups and do not prepare the body for strenuous whole-body physical demands.

More Evidence in Favor of Post-Activation Potentiation (PAP)

We have previous discussed post-activation potentiation (PAP) by which an explosive athletic performance is improved by doing heavy resistance exercise beforehand (see http://mens-fitness-and-healthdotcom.blogspot.com/2010/10/method-for-improving-explosive-physical.html).  A recent study provides further evidence of the effectiveness of this technique.

Matthews, Comfort and Crebin performed a study on ice hockey players from the English National League.

Experimental Procedure
On two different days, 11 players were timed for their maximal 25-meter sprint-speed on ice both before and 4 minutes after doing the following:

1. resting
2. sprinting while towing another skater

Results

• When the players rested between sprints, they showed no significant improvement in time between their first and second sprints.
• When the players skated against resistance following the first sprint, their second sprint took a significant 2.6% less time than their first one.

Bottom Line
This study supports others that have found improvement in explosive athletic performance when heavy resistance exercise is performed first. The resistance exercise should call upon the same muscles used in the athletic performance. Using resisted skating in this study was a good way to achieve this goal.

The Drawback of Exercising on Unstable Surfaces



Stability training, mainly in the form of lifting weights while standing on unstable surfaces, became somewhat popular with the advent of the Bosu Ball, which is a hemispheric ball about 2+ feet across mounted on a flat plastic base. The idea is that the instability of the surface brings muscles into play that are required for maintaining stability; muscles that would be minimally involved when exercising on a stable surface.

A study by Chulvi-Dedrano et al. in the Journal of Strength and Conditioning Research (vol. 24, no. 10, pp. 2723-2730, 2010) tested force production and muscle electrical activity during deadlifts on a stable surface and on two different unstable surfaces.

Method
31 young adult subjects did the following:

1. Isometric deadlift in which the lifter pulled upward maximally for 5 seconds against an immovable bar
2. Dynamic deadlift in which a barbell weighing 70% of the individual’s maximal isometric deadlift was lifted for 5 repetitions 

Lifting force was measured during the isometric efforts. Muscle electrical activity of the lower back muscles (paraspinals) was measured during both the isometric and dynamic lifts to indicate how hard the muscles were working. Both of the lifts were done on the following 3 surfaces:

1. Stable floor
2. Bosu Ball
3. T-Bow (a curved board that can rock laterally as one stands on it)

Results

• In the isometric deadlift, both the force produced and the muscle electrical activity were significantly higher on the stable surface than on either unstable surface.
• In the dynamic deadlift, muscle electrical activity was significantly higher on the stable surface than on either unstable surface

Bottom Line
This study backs up other ones that have shown that exercising on unstable surfaces does not provide as much stimulus as stable-surface training to the main muscles (prime movers) used to effect the exercise movement. It has previously been shown that more weight can be handled when lifting on stable than unstable surfaces, providing greater stimulus to the muscles. In view of these factors, training on unstable surfaces is not best for increasing the size or strength of the major muscles. However, since such training does bring stability muscles into play, it can be effectively used as a supplement to training on stable surfaces, especially for athletes who engage in sports in which maintaining stability is of major importance (e.g. hockey, figure skating, snow-boarding, gymnastics). The major part of the resistance workout should still be on stable surfaces.

Dynamic Stretching Beats Static Stretching for Team Sports

Introduction
Static stretching involves attaining a stretch to the point of mild discomfort and holding the position for at least 10 seconds. Dynamic stretching involves rapid repeated alternation between a stretched and a relaxed position.

A recent article by Amiri-Khorasani et al. in the Journal of Strength and Conditioning Research (vol. 24, no. 10, pp. 2698-2704, 2010) showed that static stretching detracts from performance on a physical agility test, while dynamic stretching tends to improve it.

Method
Nineteen professional soccer players were divided into more-experienced and less-experienced subgroups. Their performance on an agility test, which involved 14-15 seconds of changing direction and zigzagging as fast as possible around a number of cones, was tested after each of the following:

• No stretching
• Static stretching
• Dynamic stretching
• Combined static and dynamic stretching

Results

• The subjects were 4-5% slower after static and combined static/dynamic stretching than they were with either no stretching or dynamic stretching alone.
• Among the less-experienced players, dynamic stretching resulted in about 3% faster course times than no stretching.
• Among the more experienced players, there was no difference between the course times after dynamic stretching and no stretching.

Bottom Line
The evidence indicates that dynamic stretching is superior to static stretching for the kind of agility needed for most team sports. This is probably due to a reduction after static stretching in the spring-like stiffness of muscle. The results support those of other studies that have shown a detrimental effect of static stretching on strength, jumping ability and sprint speed. It is not clear why the experienced players in this study showed no advantage of dynamic stretching over no stretching at all. However, since these were professional soccer players, it seems safe to conclude that the effects on amateur athletes would parallel those on the less experienced professional players. Thus, their performance would likely be enhanced by dynamic stretching.

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.

Complex, Specific Training Improves Sports Performance

Introduction
It is much more difficult to improve the physical performance of highly trained athletes than of previously untrained subjects. Thus, it is noteworthy that the study described below by Alves et al. (Journal of Strength and Conditioning Research, vol 24, no 4, pages 936-941, 2010) produced significant performance improvement among elite young Portugese soccer players using brief exercise sessions once or twice per week.

Experimental Method
23 young elite soccer players underwent the following tests before and after an 8-week period:

• vertical jump from a static, bent-knee position
• vertical jump using a dynamic countermovement (natural quick knee bend)
• 5 meter sprint
• 15 meter sprint
• soccer agility test

All subject initially did 2 weeks of general weight training before being divided into 3 experimental groups that did the following for 6 weeks in addition to their normal soccer training:

Group 1 - Once a week, before their regular soccer training session, they went through the following 3 exercise stations:

1. 6 reps of squats with 85% of max weight, 5 meters of high-knee skipping, 5 meter sprint
2. 6 reps of calf raises with 90% of max weight, 8 vertical jumps, 3 soccer-ball high-head hits
3. 6 reps of knee extension with 80% of max weight, 6 jumps from seated position, 3 60-cm drop jumps

Group 2 - The same routine as Group 1, but done twice a week instead of once a week.

Group 3 - Control group - did no exercises supplementary to their regular soccer practice.

Results:
5-meter sprint time improved 9% for Group 1 and 6% for Group 2
15-meter sprint time improved 7% for Group 1 and 3% for Group 2
vertical jump from static bent-knee position improved 13% for Group 1 and 10% for Group 2
none of the groups improved significantly in the countermovement jumps or agility test
the control group did not improve in any of the tests

Conclusions
A relatively short exercise program of weight-lifting, jumping, and sport-specific movements performed once or twice per week can significantly improve the physical performance of elite athletes. Even though the results of the once per week and twice per week exercise groups did not differ significantly, it appears that the subjects responded better to doing the program once per week rather than twice per week when regular sport training was persued concurrently.

Static Stretching Reduces Jumping Power

Introduction
In static stretching, a muscle is stretched to the point of mild discomfort and the position is held for 15 sec or more. In contrast, dynamic stretching involves rapidly moving in and out of the stretched position. The former recommendation in favor of static stretching was based on the finding that it was effective for lasting improvements in flexibility. Thus, for many years, pre-competition static stretching was widely recommended for a broad range of athletes. However, recent studies, such as the one described below, have shown that static stretching before athletic efforts requiring explosive power (e.g. sprinting and jumping) actually hurts performance.

Study Methods
In a study by La Torre et al. (Journal of Strength and Conditioning Research, vol 24, no 3, pages 687-694, 2010), 17 young men performed vertical squat jumps from a force-detecting platform using various starting knee angles. On one day, they did the jumps after performing static stretches of their quadriceps and calf muscles for 10 minutes. Each muscle was stretched on both legs using 4 sets of 30-second holds with 30-second rests between sets. On another day they did the jumps without stretching beforehand.

Results
At all starting knee angles, stretching before the jump test reduced jump height, peak force, and maximal acceleration, but only the differences for jumps beginning with the knees least bent were statistically significant. When starting the jump with the knees flexed 50 degrees (about a half-squat position) jump height, peak force, and maximum acceleration were respectively 21%, 9%, and 15% lower when stretching was performed first than when no stretching was performed.

Bottom Line 
This study reinforces other ones showing that static stretching prior to an athletic event reduces explosive muscular power. The fact that the negative effect is most pronounced when the knees are only bent to a moderate degree is highly relevant to sports activities because most sports do not involve deeply bending the knee. Dynamic stretching does not have the same detrimental effect. Thus, it appears that before athletic events that require power but not great flexibility it is best to warm up thoroughly and perform dynamic stretches before the event. The detrimental effect of static stretching on muscular power has not been shown to carry over to the following day. Therefore, static stretching may be performed after an athletic event to promote general flexibility without harming physical performance.

Brock Lesnar's Workout - Perfect Example of Functional Training

See the video of one of Brock Lesnar's workouts. Lesnar is the current top heavyweight of the Ultimate Fighting Championship (UFC), the most popular mixed martial arts organization in the U.S. He won the NCAA heavyweight wrestling championship in 2000 and later became a professional (choreographed) wrestler. When he joined the UFC, he became a dominant force. Watch this highlight video to see his speed and power.

Lesnar's workout is a prime example of functional training. No doubt weight-lifting and running are essential for a base level of fitness. However, to really excel in a sport or other physically demanding activity, one has to train in ways that simulate the activity to be improved. Lesnar's routine is based on 5-minute rounds as are UFC fights. His exercises are mostly whole-body, multi-directional, asymmetrical, and highly taxing to the lactic-acid energy system. No doubt Lesnar does a lot of conventional weight-liting. However, his lesson to us is that, in order to excel in a sport or other physical activity, training must be supplemented by routines that simulate the target activity as to which muscles and energy systems are used and the way they are used.