Fitness Research Review

Frederick C. Hatfield II, MS, MFS, CSCS

Can you Become Stronger During the Season?

There are football coaches who note that their in-season weight training programs are designed to maintain strength levels during the season. Other coaches argue that an in-season program can promote gains despite the rigors of competitive football. Researchers at the College of New Jersey looked into the matter.

Fifty-three Division III football players were tested in the squat and bench press (1RM) before and after the season. The athletes engaged in training twice per week, performing 3 sets of 6-8 repetitions of each exercise. Significant gains were found in the squat, but not the bench press. Furthermore, the researchers found that when loads equal to or greater than 80% of their one repetition maximum produced greater strength gains than when loads less than 80% were used. Despite the lack of progress made in the bench press, researchers concluded that strength gains can be made during the season.

The Journal of Strength and Conditioning Research: Vol. 17, No. 1, pp. 109-114.

"The Stick" Doesn't Help Strength, Power or Flexibility

Research from Indiana University-Purdue University claims that the massage device popular among track athletes does not have immediate effects on strength, power or flexibility. Thirty college athletes participated in a 4 week double-blind study in which the stick or a placebo was used prior to for tests: hamstring flexibility, vertical jump, flying 20 yard dash and an isokinetic knee extension test for strength. The results did not show a difference between treatment and control group sessions.

The Journal of Strength and Conditioning Research: Vol. 16, No. 3, pp. 446-450.

Exercise Physiology Classes in High School?

With the state of health and fitness in children dwindling (as it is in most all American populations) a high school in Coral Gables, FL decided to do something about it.

Researchers from the University of Miami report on a study conducted at Coral Gables High school in which 161 students attended an exercise theory course as well as regular aerobic and resistance training sessions. Thirty-three students served as a control, only attending a biology class. Those that attended the exercise theory course and actually exercised improved significantly in the sit and reach, step test, recovery heart rate, overhead press, bench press, leg press, sit-ups, body satisfaction, and physiology knowledge.

While I expect no one was shocked to find exercise and education about exercise works, there are some interesting notes to this study. The experimental group's subjects. who far outnumbered the control group's, were chronologically older (16.5 to 15.61 years old) and had a lower percentage of body fat. This leads me to speculate that those who participated in the experimental class probably had more interest in fitness to begin with. It would be interesting to see what the effects of this program would be on those with little or no interest in fitness - in other words, the ones who probably need it the most!

The Journal of Strength and Conditioning Research: Vol. 16, No. 2, pp. 219-226.

Eccentric Training for Powerlifting?

Researchers form several universities collaborated in a study to see if extra eccentric loads would increase the lifter's 1RM in the Bench Press. The device used is interesting: a bar with a slanted bottom and hooks on the top were placed on the ends of a bar during the bench press. The length of the bar was such that once the bar touched the chest (or approached it) the device would unhook from the bar. Thus, the weight you are lowering is greater (in the study, 105%) than the load you are lifting.

Eight subjects used the device for a maximal bench press attempt and reported a 5 to 15 lbs increase in their 1RM bench press. The researchers theorized that this phenomenon was due to the enhanced stretch shortening cycle. The important question is whether or not this method will aid in training for powerlifting.

The Journal of Strength and Conditioning Research: Vol. 16, No. 1, pp. 9-13.

PNF Stretching As a Warm-Up

Proprioceptive neuromuscular facilitation (PNF) involves stretching and contracting the muscle being stretched. Researchers at Murray State University compared PNF to a general warm up routine and a general warm up routine using static stretching and it's effects on vertical jump performance. What was found is that PNF actually decreases vertical jump performance.

This is not surprising in theory. What is happening when you use this technique is a temporary detatching of the actin-myosin filaments in the muscle tissue. This in turn, temporarily reduces the number of units "pulling" to contract the muscle. Many knowledgeable coaches prescribe PNF after training instead of before for this reason.

The Journal of Strength and Conditioning Research: Vol. 15, No. 3, pp. 332-336.

Weight Lifting Prior to Sprinting?

Researchers at the University of Memphis and The University of Mississippi are theorizing that a single set of squats before engaging in sprints may help sprinters lower their times.

Nine subjects were studied in 3 different trial. The methods used in these trials are:

Trial 1: 90% of 1RM/ 10 reps x 1 set followed immediately by a 10 second sprint cycle test.

Trial 2: 90%/10 x 1 followed by 5 minutes of rest before a 10 second sprint cycle test.

Trial 3: 90%/10 x 1 followed by 20 minutes of rest before a 10 second sprint cycle test.

The results showed that the group using a 5 minute rest period had significantly higher average power and average power relative to body weight over the other two groups. What was not studied was a trial with no squats before a 10 second sprint cycle test. It was concluded that, "this particular squat protocol could have a potential carry-over effect into improvements in 100-m sprint times when performing the squats 5-minutes prior to performance."

Several possibilities exist. Squatting 90% for a set of 10 reps is quite a load! It's possible that the squats "primed" the nervous system, but muscle tissue was too fatigued to engage in testing immediately. When the subjects waited 20 minutes may have allowed the muscle tissue to recover, but the priming effect of the nervous system may have been long gone. Five minutes however, was enough rest but the nervous system stayed in an excited state. A stretch shortening cycle or higher hormonal levels may have been involved in the first and possibly the second trial, it would not have an effect after 20 minutes. Whether or not other lifting loads would have produced different results is not reported in the abstract.

The Journal of Strength and Conditioning Research: Vol. 15, No. 3, pp. 344-348.

Should Football Players Compete in Winter Sports?

Researchers in Columbus, OH were concerned with whether football players should be encouraged to participate in other sports or hit the weights in preparation for the next season. Fifty-seven high school athletes from 3 different schools participated in one of two groups. One group participated in an off-season weight training program while the other participated in the same weight training program, but also competed either in basketball or wrestling. Several tests including body composition, muscle strength, muscle power and agility were tested after the football and winter sport season. Here is a table of the results:

TEST WEIGHT TRAINING GROUP WEIGHT TRAINING + WINTER SPORTS GROUP

Body weight Increase Increase

Body fat percentage Increase Increase

1RM Bench press Increase Increase

1RM Squat Increase No increase

Vertical jump Increase Increase

Seated shot put No increase Increase

Agility (18.3-M Agility Run [Ag]) Increase No increase

The results listed above lead the researchers to conclude, "There appears to be no clear advantage to devoting time solely to strength training." However, the most surprising note of this data is that winter sports and weight training appear to do nothing to keep body fat levels from increasing.

The Journal of Strength and Conditioning Research: Vol. 15, No. 1, pp. 132-135.