Impact of training patterns on incidence of illness and injury during a women's collegiate basketball season.

This study was conducted to monitor the training patterns throughout a basketball season in order to determine if a relationship exists between the physical stress of practice and the occurrence of injuries and illnesses in NCAA Division III athletes. Subjects consisted of college women (n = 12) ranging in age from 18 to 22 years. A certified athletic trainer distributed a questionnaire following each practice, including 2 weeks of preseason, documenting the presence of injury, illness, or both, relative to the intensity and duration of practice. Training load, training monotony, and training strain were computed using the session rate of perceived exertion scale method. An increase in injuries occurred during times of increased training loads, particularly during the first 2 weeks of formal practice, and immediately subsequent to the holidays. The temporal relationship between training load and injury suggests a causative link (p < 0.01; r = 0.675). The present data suggest that the periodization pattern of basketball training may be linked to the likelihood of illness/injury.

Effect of resistance exercise volume and complexity on EMG, strength, and regional body composition.

This study was designed to examine the effects of a 12-week resistance training program using single versus multiple sets of a complex versus simple exercise on EMG, strength and regional body composition. Twenty-eight untrained men ( n=15) and women ( n=13) performed resistance training twice per week. Group 1 (S-1, n=9) performed one set of a leg press (LP) and bicep curl (BC) exercise, group 2 (M-6, n=9) performed six sets of a LP and BC exercise, and group 3 (C, n=10) was the control group. One-repetition maximums (1RMs) and EMG were measured in the LP and BC during pre-, mid-, and post-training. Lean body mass of the legs and arms were measured pre- and post-training by dual energy X-ray absorptiometry. Results of the study indicated that both S-1 and M-6 groups significantly increased percentage strength pre- to post-training in both the LP and BC [S-1 pre-/post-LP=41.2 (23.7)%, BC=8.5 (6.71)%; M-6 pre-/post-LP=52.6 (12.6)%, BC=22.8 (15.6)%; mean (SD)]. However, compared to S-1, M-6 showed a significantly greater increase in percentage strength in the BC ( P

Characteristics of titin in strength and power athletes.

The purpose of this investigation was to identify characteristics of the muscle protein titin in different athletic populations with increased levels of strength and power relative to non-athletes. Subjects fell into one of four groups: (1) non-athletes (NA) ( n=5), (2) weightlifters (WL) (n=5), (3) powerlifters (PL) (n=5), (4) sprinters (S) (n=5). A one repetition maximum in the squat exercise was performed to assess strength. In addition, countermovement vertical jump trials were performed to assess power capabilities. Peak power (W(peak)) was calculated for the vertical jumps from force plate measurements. From gel electrophoresis analyses of muscle samples, titin-1 (T1) and titin-2 (T2) protein bands were identified, quantified and expressed relative to each other. In addition the relative mobility (R(f)) of T1 and T2 was determined as an estimate of molecular weight. The NA group [%T1=47.8 (5.1), %T2=52.2 (5.1), mean (SE)] had lower T1 and higher T2 percentages than WL [%T1=62.3 (6.6), %T2=37.7 (6.6)], PL [%T1=66.8 (5.0), %T2=33.2 (5.0)] and S [%T1=65.9 (4.9), %T2=34.1 (4.9)] groups (P< or =0.10, preliminary investigation into titin and exercise justifies more liberal alpha level). No significant differences were found in R(f) of T1 or T2 between the groups. This investigation has shown that there is a differential expression of titin protein bands in competitive athletes with increased levels of strength and power in comparison to untrained non-athletic individuals. Some relationships between titin characteristics and athletic performance were observed; however, no conclusions can be made based on these data as to the contribution of titin to strength or power capabilities.

Effects of heavy resistance/power training on maximal strength, muscle morphology, and hormonal response patterns in 60-75-year-old men and women.

Eleven women (TRW; 64 +/- 4 yrs) and ten men (TRM; 65 +/- 5 yrs) participated in the strength/power training twice a week for 24 weeks. Basal concentrations of serum total and free testosterone, growth hormone (GH), dehydroepiandrosterone sulfate (DHEAS), cortisol and sex hormone binding globulin (SHBG) as well as acute responses of serum total and free testosterone, growth hormone (GH) were measured. Maximal 1RM strength in the squat, chair rise time and muscle fibre distribution and areas of type I and IIa and IIb of the vastus lateralis were also examined. 1RM squat increased in TRW by 26 (SD10)% (p < .001), and in TRM by 35 (7)% (p < .001) and chair rise time improved in both groups (p < .001). Fibre areas increased in type I, (p < .01), IIa (p < .01) and IIb (p < .01) in TRM and type I (p < .05) and IIa (p < .05) in TRW. The proportion of type IIa increased from 31% to 43% (p < .05) in TRW and that of type IIb decreased from 27% to 17% (p < .05) in TRW and from 25% to 17% (p < .05) in TRM. Individual concentrations of testosterone/cortisol ratios correlated (r = 0.63; p < .05) with the individual increases in 1RM strength in TRW. The exercise sessions resulted in acute increases in serum GH in both groups (p < .05) with a further increase (p < .01) up to 10 minutes post-loading in TRM at post-training.

The effect of heavy- vs. light-load jump squats on the development of strength, power, and speed.

The purpose of this investigation was to examine the effect of an 8-week training program with heavy- vs. light-load jump squats on various physical performance measures and electromyography (EMG). Twenty-six athletic men with varying levels of resistance training experience performed sessions of jump squats with either 30% (JS30, n = 9) or 80% (JS80, n = 10) of their one repetition maximum in the squat (1RM) or served as a control (C, n = 7). An agility test, 20-m sprint, and jump squats with 30% (30J), 55% (55J), and 80% (80J) of their 1RM were performed before and after training. Peak force, peak velocity (PV), peak power (PP), jump height, and average EMG (concentric phase) were calculated for the jumps. There were significant increases in PP and PV in the 30J, 55J, and 80J for the JS30 group (p

American College of Sports Medicine position stand. Progression models in resistance training for healthy adults.

In order to stimulate further adaptation toward a specific training goal(s), progression in the type of resistance training protocol used is necessary. The optimal characteristics of strength-specific programs include the use of both concentric and eccentric muscle actions and the performance of both single- and multiple-joint exercises. It is also recommended that the strength program sequence exercises to optimize the quality of the exercise intensity (large before small muscle group exercises, multiple-joint exercises before single-joint exercises, and higher intensity before lower intensity exercises). For initial resistances, it is recommended that loads corresponding to 8-12 repetition maximum (RM) be used in novice training. For intermediate to advanced training, it is recommended that individuals use a wider loading range, from 1-12 RM in a periodized fashion, with eventual emphasis on heavy loading (1-6 RM) using at least 3-min rest periods between sets performed at a moderate contraction velocity (1-2 s concentric, 1-2 s eccentric). When training at a specific RM load, it is recommended that 2-10% increase in load be applied when the individual can perform the current workload for one to two repetitions over the desired number. The recommendation for training frequency is 2-3 d x wk(-1) for novice and intermediate training and 4-5 d x wk(-1) for advanced training. Similar program designs are recommended for hypertrophy training with respect to exercise selection and frequency. For loading, it is recommended that loads corresponding to 1-12 RM be used in periodized fashion, with emphasis on the 6-12 RM zone using 1- to 2-min rest periods between sets at a moderate velocity. Higher volume, multiple-set programs are recommended for maximizing hypertrophy. Progression in power training entails two general loading strategies: 1) strength training, and 2) use of light loads (30-60% of 1 RM) performed at a fast contraction velocity with 2-3 min of rest between sets for multiple sets per exercise. It is also recommended that emphasis be placed on multiple-joint exercises, especially those involving the total body. For local muscular endurance training, it is recommended that light to moderate loads (40-60% of 1 RM) be performed for high repetitions (> 15) using short rest periods (< 90 s). In the interpretation of this position stand, as with prior ones, the recommendations should be viewed in context of the individual's target goals, physical capacity, and training status.