Skip navigation

Monthly Archives: April 2011

Comfort et al published an article in the May issue of the Journal of Strength and Conditioning Research on power clean variations. This is an interesting article because it may have some implications for strength and conditioning practices.

There are many variations to the clean used in strength and conditioning. Probably the most common is the power clean (where the bar is received in a partial squat). The power clean is performed from the floor (called a power clean), or from various “hanging” starting positions (means that the starting position is not from the floor, but the lifter is supporting the weight). Hanging positions include having the barbell start from above the knees, start from knee height, or start from below the knee height.

Normally, the power clean is taught through a series of progressions. First it is taught from above the knees, then the knees, etc. until finally the exercise is being performed from the floor. The thinking is that the from the floor version is the most preferred as the athlete is handling the most weight and generating the most power from that position.

The Comfort et al study casts some doubt on that practice.

They studied eleven elite male rugby athletes. The athletes performed sets of three repetitions with 60% of their 1-RM power clean while standing on a force platform. One set of three was performed with each of the following variations:
• Power clean (floor)
• Hang power clean, knees
• Hang power clean, above the knees
• Hang clean pull, above the knees

The findings are interesting:
• There were significant differences in terms of peak ground reaction forces between the variations. The hang (above the knees) and hang pull both resulted in almost 3000 newtons, whereas the floor and knee variations did not even generate 2500 newtons.
• There were significant differences in terms of rate of force development between the variations. The hang (above the knees) and hang pull both resulted in almost 15,000 N/s whereas the floor and knee variations did not even generate 10,000 N/s.

These results call current practices into question. It’s possible that the hang, above the knee and hang pull may be more beneficial for power output than performing the lift from the floor. This is beneficial in the sense that it is easier to teach these exercises.

Now, some caution needs to be taken with interpretation of these results. It’s possible that the athletes were not using good form on the lifts and this form could have had a major influence on the results. It’s possible that the athletes may not have been very experienced at the knee or floor variations, which would have influenced the results. It’s also possible that these results may only apply to this particular population (i.e. there may be something unique about the combination of their body structure, conditioning background, technique, etc. that caused these results).

This would be an interesting area to see more research on, with a wider subject pool. If the lifts from the hang result in the greatest power outputs and greatest rates of force development, then why waste an athlete’s time performing any other variation?

Comfort, P., Allen, M., and P. Graham-Smith. (2011). Comparisons of peak ground reaction force and rate of force development during variations of the power clean. Journal of Strength and Conditioning Research, 25(5), 1235-1239.


Elliott et al published a study in the April issue of the American Journal of Sports Medicine looking at hamstring injuries in NFL football players over a 10 year period, 1989-1998. This information is drawn from information that the teams’ athletic trainers submit to the NFL based upon uniform reporting definitions.

Over this 10-year period, players on NFL teams experienced almost 1720 hamstring strains, with about 20% being severe and the rest evenly split between being minor and moderate. Minor injuries result in less than seven days of missed participation, 7-21 are moderate, 21+ are severe. Almost 17% of those hamstring strains were re-injuries.

Almost 53% of the hamstring injuries occurred during practices with the rest occurring during games.

More than 53% of the hamstring injuries occurred during the pre-season. In fact:
• 80% of all practice injuries occurred during the pre-season
• 22% of game-related injuries occurred during the pre-season

In terms of position and injuries, the following positions sustained the highest number of injuries:
• Defensive secondary (23%)
• Wide receivers (21%)
• Special teams (13%)
• Running backs (12%)
• Linebackers (12%)

The first thing that needs to be kept in mind with this information is that it is dated, even since 1998 players are larger and both practices and the season are a little different. The second important thing is that it applies to a very specific population.

The observation that a lot of the injuries are occurring in pre-season indicates a lack of off-season preparation. In other words, the injuries are occurring as the players are getting back into shape.

While this information is applicable to a really specific population, it’s something that can be examined for any coach’s specific situation. This type of information tells us that there’s a need for a more consistent off-season program, it tells us which positions get injured the most (so that their position-specific workouts can be tailored to preventing these injuries), and it gives us a good idea of when these injuries occur so that we can prepare for that.

Elliott, M.C.C.W., Powell, J.W., and C.D. Kenyon. (2011). Hamstring muscle strains in professional football players: A 10-year review. American Journal of Sports Medicine, 39(4): 843-850.

Brughelli et al had a really interesting study in the April issue of the Journal of Strength and Conditioning Research looking at running velocity and its relationship with kinetic and kinematic variables.

The authors studied 16 Australian Rules football players. Subjects determined their maximum running velocity on a Woodway nonmotorized treadmill, then ran at 40, 60, 80, and 100% for the study. They were given four seconds to reach the velocity to be examined and maintained it for five seconds. They were given long rest periods between bouts (greater than three minutes).

Results from the study:
As you would expect, vertical and horizontal force increased as velocity increases, contact time decreases, and both stride length and frequency increase. The specific are interesting. From 40% to 100%:
• Vertical force increased by 18%
• Horizontal force increased by 102%
• Contact time decreased by 31%
• Stride length increased by 92%
• Stride frequency increased by 108%

The fact that both stride length and frequency increase as velocity increases underscores the need to train both when seeking to improve sprinting.

The vertical and horizontal force results are interesting. The authors point this out, but the results indicate how important horizontal force is and that maybe vertical force isn’t as important at increased velocities. This is actually an important point for conditioning as most strength training is geared towards increasing vertical force (squats, deadlifts, cleans, snatches). This suggests that if the focus is on sprinting speed, one needs to find a way to improve horizontal force which would be split versions of lifts along with horizontal plyometrics.

The second part of their study was to run correlations between the variables and compare them to maximum running velocity. Only two variables were significant, horizontal force and stride length (r’s of 0.47 and 0.66 respectively). No other variable had an r higher than 0.28. This underscored the importance of horizontal force to maximum velocity.

Brughelli, M., Cronin, J., and A. Chaouachi. (2011). Effects of running velocity on running kinetics and kinematics. Journal of Strength and Conditioning Research, 25(4), 933-939.

The Texas Comptroller published a report on State Health Care Spending. The report begins by pointing out that between 2005 and 2009, the state’s spending on health care has increased by over 36%. Which is four times as fast as inflation and population growth. In 2009, the state spent over $30 billion on health care and this represents a third of all state spending.

The report is organized into background information, an analysis of how the state spends money on health care, cost drivers, and proposals.

In fiscal year 2009, the state’s spending on health care is split as follows:
• Medicaid and CHIP: 68%
• Other: 21%
• State Employee and Retiree Medical Benefits: 6%
• Mental Health Services: 3%
• Prisoner Health Care: 2%

State Expenditures:
Five state agencies account for the bulk of health care spending:
• Health and Human Services Commission (HHSC): 58%
• Department of Aging and Disability Services (DADS): 20%
• Other Agencies and Higher Education Institutions: 11%
• Department of State Health Services: 6%
• Employee Retirement System: 4%
• Department of Criminal Justice: 2%

HHSC and DADS primarily spend for Medicaid. The comptroller notes that:
• Non-disabled children make up most of the Medicaid population, 53% of beneficiaries, but only 29% of Medicaid spending on direct health care services.
• Aged, blind, and disabled account for 31% of Medicaid clients and 58% of the program’s expenditures.

DADS administers long-term Medicaid services for the elderly and disabled, this breaks down as follows:
• Nursing facilities: 35%
• Other services: 28%
• Home and community based services: 11%
• State school services: 10%
• Primary home care: 8%
• Community based alternatives: 8%

With regards to the Department of State Health Services, the Comptroller’s report is primarily concerned with the providing of mental health services.

The report points out that expenditures for state employees and retiree medical benefits rose by 34% from 2005 to 2009.

Cost Drivers:
A number of things are increasing the costs of health care:
• Technological advances in products, services, and drugs
• Health insurance pays approximately 85% of health care costs (with out-of-pocket costs making up at 15%), compared to only 45% in 1960.
• Increased reliance on specialists for medical treatment
• Shortages of health care professionals in West, South, and Panhandle areas of Texas
• Lifestyle choices
• Lack of access to prenatal care

With regards to state employee and retirees, the report notes that the following are driving up costs:
• Medical inflation: the amount paid for outpatient visits form 2008 to 2009 rose by almost 22%
• Increased emergency room usage
• Increased use of high-tech radiology
• Specialty drugs: the cost for specialty drugs increased by 694% from 2000 to 2009
• Aging of ERS members

The report has a number of proposals to help reign in health care costs. Later, we’ll discuss the legislative action required and the status of those bills as of 20 April 2011.
• Expand STAR and STAR+PLUS managed care plans
• Provide dental services in the managed care arrangement
• Convert HHSC’s primary care case management areas to the STAR managed care model
• Include Medicaid inpatient hospital services in the STAR+Plus plan
• Reduce hospital payments for preventable readmissions
• Institute a statewide smoking ban
• Create step-down alternatives for individuals who have been in state mental hospitals but do not require full hospitalization
• Undertake cleanliness initiatives in state hospitals
• Require state and higher ed employees to pay a portion of health care benefits based on their years of service
• Require tobacco users to pay more for their health insurance benefits
• Charge state employee dependents a higher premium if they turn down coverage offered by their employers to join ERS
• Allow ERS to offer varying plans to increase member cost sharing
• Allow retirees to opt out of ERS coverage in lieu of a Medicare supplemental policy paid by state funds
• Reduce prison terms for certain elderly, non-violent offenders
• Evaluate the Medically Recommended Intensive Supervision Program for potential savings
• Increase physician workforce

The table below shows each option, the estimated savings for the biennium in all funds, the bills that have been filed in the Texas Legislature to achieve these options, and their status as of April 20, 2011. At this late date, any bill that is not out of committee is probably dead.

Proposal Estimated Savings (all funds) Bills Status
Expand STAR and STAR+PLUS $732 million SB 23 (Nelson)

SB 1181 (Duncan)

HB 1645 (Zerwas)

Testimony taken in committee

Referred to committee

Left pending in committee

Dental Services $175 million SB 23 (Nelson)

SB 1181 (Duncan)

HB 1645 (Zerwas)

Testimony taken in committee

Referred to committee

Left pending in committee

Convert Primary Care Case Management to STAR $93 million SB 23 (Nelson)

SB 1181 (Duncan)

HB 1645 (Zerwas)

Testimony taken in committee

Referred to committee

Left pending in committee

Inpatient Hospital Services $58 million SB 23 (Nelson)

SB 1181 (Duncan)

HB 1645 (Zerwas)

Testimony taken in committee

Referred to committee

Left pending in committee

Preventable Readmissions Unknown SB 7 (Nelson) Received from the Senate
Smoking Ban $15 million HB 670 (Crownover)

SB 355 (Ellis)

Considered in calendars

Not again placed on intent calendar

Step Down Alternatives $6 million SB 7 (Nelson) Received from the Senate
Cleanliness Initiatives Unknown HB 1657 (Davis)

SB 620 (Nelson)

Left pending in committee

Received from the Senate

Employees Paying Portion of Expenses $112 million HB 1

SB 1

Scheduled for public hearing (Senate Finance committee)

In committee

Tobacco Users Pay More for Benefits $118 million HB 1166 (Zerwas) Left pending in committee
State Employee Dependents Unknown HB 3373 (Murphy) Left pending in committee
ERS Plan Flexibility Unknown HB 1766 (Crownover)

B 1362 (Laubenberg)

Report sent to calendars

Refereed to committee

Retiree Opt Out Unknown HB 3496 (Darby) Referred to committee
Elderly Prison Terms Unknown HB 3366 (White)

HB 3763 (Marquez)

Left pending in committee

Referred to committee

MRIS Program Unknown HB 3538 (Thompson)

HB 3761 (Marquez)

Left pending in committee

Referred to committee

Each of these options has significant ripple effects, it is worth reading the full report to see the Comptroller’s analysis of the pro’s and con’s of each option. The full report can be found here:

Hartwig et al published a really smart study in the Journal of Strength and Conditioning Research examining how adolescents play rugby and comparing that with how they train. This study is an example of how sophisticated we can be with regards to determining the speed and conditioning needs of team sport athletes.

The authors examined the games and training sessions for ten adolescent rugby teams at three levels; school boy, national representative, and high performance talent squats. They analyzed over 84 training sessions (approximately 188 hours) and 20 games (approximately 33 hours). To perform this analysis, they divided the movement patterns into the following:
• Stationary (0-1 km/h)
• Walking (1-7 km/h)
• Jogging (7-12 km/h)
• Striding (12-21 km/h)
• Sprinting (21+ km/h)

Basically the authors found that the way the athletes move in training is very different from how they move in games. Highlights of the results:
• An equivalent amount of time is spent being stationary and walking between training and competition.
• More time is spent in the higher intensity movements during competition:
o Jogging: 14% of game vs. 8% of training

o Striding: ~3% of game vs. ~1% of training
o Sprinting: ~1% of game vs. .1% of training

This information is also broken down in terms of sprints per hour of play, sprint duration, maximum sprint duration, sprint distance, etc. All of this information is provided for the aggregate as well as breaking it down for forwards and backs.

The data from the article suggest a need to really address the conditioning of the athletes for better transfer over to the game. Articles like this have been written for basketball and for soccer, but this is the first one I’ve seen on rugby like this. In those articles, the movement patterns are defined and the sport/positions are analyzed over a series of games.

One has to be cautious with articles like this. The results only apply to the population studied. Older athletes, at a more advanced level of competition, will experience the games differently. So, while this information is very interesting it needs to be kept in mind that one will have to do this kind of analysis for your unique situation.

Hartwig, T.B., Naughton, G., and J. Searl. (2011). Motion analyses of adolescent rugby union players: A comparison of training and game demands. Journal of Strength and Conditioning Research, 25(4), 966-972.

Kell et al, in the April volume of the Journal of Strength and Conditioning Research published a study looking at whole-body strength training and its effect on nonspecific lower back pain (NSLBP). NSLBP is the kind suffered by around 90% of people with LBP and refers to pain that cannot be seen (i.e. it is not the result of a herniation, bulge, or other mechanical injury).

The authors studied 240 subjects who had suffered NSLBP for 37 months (on average). Subjects were broken up into one of four groups: 2D, 3D, 4D, and Control. 2D trained two days/week, 3D three days/week, 4D four days/week, and control did not exercise.

The workouts consisted of total body strength training; leg presses, leg extensions, leg curls, bench press, incline press, pull-downs, cable rows, dumbbell shoulder presses, arm curls, pushdowns, crunches, Swiss ball crunches, and prone supermans.

Groups 2D and 3D trained their entire body each session. 4D split their workouts up into legs/shoulders/biceps/core and chest/back/triceps/core and did each workout twice a week. Each group had three weeks of familiarization followed by three three-week blocks of training, each block separated by a week of testing. The weights become progressively heavier during the study (eventually 80% of 1-RM) while the volume fluctuated throughout the study. As expected, the 2D had the lowest training volume, followed by 3D, followed by 4D.

At the end of the study:
• 3D and 4D increased their body mass by around 2kg.
• 3D and 4D decreased their body fat by around 2%.
• All groups increased their strength measures, 4D greater then 3D, 3D greater than 2D (with the exception of bench press, where 2D and 3D increased by an equivalent amount).

The above results show that the training was difficult enough and long enough to produce a training effect. The interesting point is its impact on the subjects’ perceptions of pain and disability.

Group Pain Pre Pain Post Pain Change Disability Pre Disability Post Disability Change




























The trend is that the more the subjects exercised, the more their perceptions of pain and disability decreased. All treatments had a statistically significant effect, but the 4D group had the greatest gains.

Three and four days of training per week allows for a greater training volume. The workouts are shorter, but they are repeated more frequently. This is beneficial to any individual because the greater volume provides a greater training effect to the body. The four days/week also breaks the workouts up so that they are shorter, allowing for greater intensity on each exercise.

The workouts used in this study are pretty straightforward, a total body approach to strength training with a mixture of free weights, dumbbells, bodyweight exercises, and selectorized equipment. There aren’t a lot of “core” exercises; merely crunches, prone supermans, and stability ball crunches. This study suggests that merely improving a person’s fitness level may be enough to have an impact on LBP.

Kell, R.T., Risi, A.D., and J.M. Barden. (2011). The response of persons with chronic nonspecific low back pain to three different volumes of periodized musculoskeletal rehabilitation. Journal of Strength and Conditioning Research, 25(4), 1054-1062.

I was asked to post some thoughts on the biggest breakthroughs in strength training over the last 25 years. I’m going to divide my thoughts into four categories: training breakthroughs, marketing breakthroughs, research breakthroughs, and discipline breakthroughs.

Training Breakthroughs:
There are several major training breakthroughs over the last 25 years, though these have not all been positives:
• The ascension of periodization: With the break-up of the Eastern European communist block, the influx of their writings and experts, and with the core scientists in strength and conditioning having an Olympic weightlifting background, periodization of training is king when it comes to strength and conditioning. Elsewhere I have thoughts on the limitations on what we know, what I’ll say here is that there has been an interesting attempt to control the language associated with periodizaiton. For example, linear, nonlinear, conjugate, block, unplanned, etc.
• Bulgarian training approaches to Olympic-style weightlifting: This is specificity personified. Have the weightlifters snatch, clean, jerk, and front squat very heavy several times a day. Like a lot of training approaches, because it worked in a small and limited population it has been widely copied elsewhere. Personally I think this approach has really set back American Olympic lifting.
• Westside barbell: The Westside barbell approach has really had an influence on powerlifting and on the strength and conditioning of athletes. Analyze your weaknesses, train your weaknesses, repeat. It also brings back the old school idea of breaking movements down into their components to train weaknesses.
• Attempts to get a handle on speed and agility training: Speed is poorly understood outside of track and field. Agility is poorly understood period. In the last 25 years there has been a real attempt to get a better handle on how to coach these two aspects of training. Sometimes borrowing from track and field, sometimes borrowing from motor learning, sometimes just trying things and seeing how they work.

Marketing Breakthroughs:
Marketing has a huge impact on the strength and conditioning field. What is always challenging about this fact is that educated professionals can rarely be counted on to do their homework and succumb to things that sound good. These include:
• Core training: Again, I’ve voiced my thoughts on this in several areas. I do think this has been really valuable from the standpoint that it gets people into the gym, and ultimately anything that does that is a good thing.
• Functional training: At the end of the day, anything that makes you stronger, more powerful, faster, more mobile, etc. is functional training. But coining this term was genius because it implies that anything that doesn’t fit under this term is not functional. Again, anything that ultimately gets people into the gym is a good thing.
• Assorted implements: There must be a magic exercise, drill, or piece of equipment out there. Bands, unstable devices, balls, kettle bells, etc. are all examples.

Research Breakthroughs:
Over the last 25 years, strength and conditioning has been researched extensively. In my opinion, the following are the major breakthroughs as a result of research:
• Static stretching and warm-up: Static stretching as warm-up seems to interfere with power and speed. This was really important research for the preparation of athletes and completely changed how all of us approach this.
• Understanding of how the squat works: After Karl Klein’s study, many were scared of the back squat exercise. Today we have a great understanding of how the squat exercise impacts the structures of the knee and it conflicts with Klein’s conclusions.
• Power development: There has been a lot of significant research, especially out of Australia, on how the body develops power. Everything from weighted jumps, complex training, contrast training, slow strength exercises, fast strength exercises, plyometrics, and the Olympic lifts.
• Recognition of gaps: Over the last 25 years, we’ve realized that we don’t “know” what we think we know. This includes core training, periodization, velocity specificity, the neural adaptations from training, etc.

Discipline Breakthroughs:
Over the last 25 years, strength and conditioning has emerged as a discipline and a career field:
• Strength and conditioning coaching: Most universities, semi-professional, and professional teams have strength and conditioning coaches today. People go to school and work their way up a career ladder to be a strength and conditioning coach. Now, this has lead to a lot of issues that are common with other coaches including job security, qualifications, demands for licensure, injuries to athletes, and the good old boy network, but it’s something that didn’t really exist 25 years ago.
• Professional associations: Professional associations, attempting to link research to practice, now exist to disseminate information on strength and conditioning. This has been a positive from the information dissemination standpoint. It’s a negative because these associations become people’s careers, become dogmatic, and end up existing to exist as opposed to serve their populations.

Anyway, my $0.02 on the breakthroughs of the last 25 years with strength and conditioning.