Low-Load vs. High-Load Resistance Training to Failure on One Repetition Maximum Strength and Body Composition in Untrained Women.

Dinyer, TK, Byrd, MT, Garver, MJ, Rickard, AJ, Miller, WM, Burns, S, Clasey, JL, and Bergstrom, HC. Low-load vs. high-load resistance training to failure on one repetition maximum strength and body composition in untrained women. J Strength Cond Res 33(7): 1737-1744, 2019-This study examined the effects of resistance training (RT) to failure at low and high loads on one repetition maximum (1RM) strength and body composition (bone- and fat-free mass [BFFM] and percent body fat [%BF]) in untrained women. Twenty-three untrained women (age: 21.2 ± 2.2 years; height: 167.1 ± 5.7 cm; body mass: 62.3 ± 16.2 kg) completed a 12-week RT to failure intervention at a low (30% 1RM) (n = 11) or high (80% 1RM) (n = 12) load. On weeks 1, 5, and 12, subjects completed 1RM testing for 4 different exercises (leg extension [LE], seated military press [SMP], leg curl [LC], and lat pull down [LPD]) and a dual-energy x-ray absorptiometry scan to assess body composition. During weeks 2-4 and 6-7, the subjects completed 2 sets to failure for each exercise. During weeks 8-11, the subjects completed 3 sets to failure for each exercise. The 1RM strength increased from week 1 to week 5 (LE: 18 ± 16%; SMP: 9 ± 11%; LC: 12 ± 22%; LPD: 13 ± 9%), week 1 to week 12 (LE: 32 ± 24%; SMP: 17 ± 14%; LC: 23 ± 26%; LPD: 25 ± 13%), and week 5 to week 12 (LE: 11 ± 9%; SMP: 7 ± 9%; LC: 10 ± 7%; LPD: 11 ± 11%) in each exercise, with no significant differences between groups. There were no significant changes in BFFM (p = 0.241) or %BF (p = 0.740) for either group. Resistance training to failure at 30% 1RM and 80% 1RM resulted in similar increases in 1RM strength, but no change in BFFM or %BF. Untrained women can increase 1RM strength during RT at low and high loads, if repetitions are taken to failure.

Complications of Spinal Cord Injury Over the First Year After Discharge From Inpatient Rehabilitation.

OBJECTIVES: To describe the prevalence and cumulative incidence of secondary complications of spinal cord injury (SCI) in the first year after discharge from inpatient rehabilitation (IR); and to evaluate potential associations between risk of complications and sociodemographic and injury-specific factors. DESIGN: Secondary analysis of data collected for a single-site, single-blind, randomized controlled trial comparing telephone follow-up with usual care. SETTING: Inpatient rehabilitation units. PARTICIPANTS: Adults ages ≥18 years (N=169) within 1 year of discharge from IR after SCI. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Self-report of 10 secondary complications of SCI. RESULTS: Participants experienced a mean of 4.7 complications over 12 months. The most frequently reported complications were urinary tract infection (UTI), autonomic dysreflexia (AD), and pressure ulcers, with cumulative incidences of 62%, 43%, and 41%, respectively. Bone and soft tissue injuries (cumulative incidence, 35%) and bowel problems, including impaction or severe constipation (cumulative incidence, 33%), were also common. Cumulative incidences of AD, decubitus ulcers, UTI, and problems with bladder were greater in participants with higher level and more complete injuries, and some recurrent complications were common. Age at injury and impairment level significantly affected rates of complications, and subjects developed an average of 2.33 distinct complications during the study period. CONCLUSIONS: People with SCI are at high risk for a number of secondary complications over the first year after discharge from IR. Although these data offer some insight into who with SCI is at highest risk for first time and recurrent complications, further study is needed to refine this understanding and to develop effective educational and prevention strategies.

Increasing Lean Mass and Strength: A Comparison of High Frequency Strength Training to Lower Frequency Strength Training.

The purpose of this study was to determine the effect strength training frequency has on improvements in lean mass and strength. Participants were 7 women and 12 men, age (χ̄= 34.64 years ± 6.91 years), with strength training experience, training age (χ̄= 51.16 months ± 39.02 months). Participants were assigned to one of two groups to equal baseline group demographics. High frequency training group (HFT) trained each muscle group as the agonist, 3 times per week, exercising with 3 sets per muscle group per session (3 total body workouts). Low frequency training group (LFT) trained each muscle group as the agonist one time per week, completing all 9 sets during that one workout. LFT consisted of a routine split over three days: 1) pectoralis, deltoids, and triceps; 2) upper back and biceps; 3) quadriceps, hamstrings, calves, and abdominals. Following eight weeks of training, HFT increased lean mass by 1.06 kg ± 1.78 kg, (1.9%), and LFT increased lean mass by .99 kg ± 1.31 kg, (2.0%). HFT strength improvements on the chest press was 9.07 kg ± 6.33 kg, (11%), and hack squat 20.16 kg ± 11.59 kg, (21%). LFT strength improvements on chest press was 5.80kg ± 4.26 kg, (7.0%), and hack squat 21.83 kg ± 11.17 kg, (24 %). No mean differences between groups were significant. These results suggest that HFT and LFT of equal set totals result in similar improvements in lean mass and strength, following 8 weeks of strength training.

Prevalence of Exercise-Induced Bronchoconstriction Measured by Standardized Testing in Healthy College Athletes.

BACKGROUND: Exercise-induced bronchoconstriction (EIB) can lead to long-term respiratory illness and even death. EIB prevalence rates are both high and variable in college athletes. Prevalence rates may be underestimated due to ineffective testing and screening. The purpose of this study was to investigate the prevalence of EIB in college athletes by a standardized EIB test that can be used on many college campuses. In addition, we assessed the usefulness of self-reporting EIB/asthma (1) history, (2) symptoms, and (3) respiratory medication obtained from a simple screening questionnaire for predicting an EIB-positive athlete. METHODS: A standardized EIB test and self-report questionnaire were administered to college athletes on 10 different sports teams. Information collected included pulmonary function (spirometry), expired gas analysis (maximal oxygen uptake), CO2 production, minute ventilation, EIB/asthma history, current symptoms, and medication use. RESULTS: Results showed that 34 of 80 athletes (42.5%) were EIB-positive by standardized exercise testing. The majority (76.5 and 58.8%) of the 34 athletes who tested positive self-reported a negative history or no symptoms, respectively. Also, 79.4% of the athletes who tested positive for EIB reported not using a respiratory medication. There were no significant differences in a positive EIB test when assessing interactions for history (P = .93), current symptoms (P = .12), or respiratory medication use (P = .66). CONCLUSIONS: A high proportion of college athletes tested positive for EIB when using a standardized test. Positive history, current symptoms of EIB/asthma, and respiratory medication use were not predictive of a positive test. Many EIB-positive athletes are not using a respiratory medication. More work is needed to develop an effective screening tool and improve education for EIB in college athletes.

Resistance and Aerobic Training Sequence Effects on Energy Consumption in Females.

The objective of this study was to investigate the effect of sequence of resistance and aerobic training on energy consumption on sedentary overweight females. Participants were 15 sedentary overweight females (age = 28.6 ±12 yrs; BMI = 28.1±7.8) Subjects did a counterbalanced intervention: resistance training (circuit training) first (intervention RT) or aerobic exercise first (intervention AT), while oxygen consumption was continuously measured for 80 min. Subjects performed a warm-up on the treadmill at 40% of their heart rate reserve for 5 minutes, then for 30 minutes did continuous walking or jogging on the treadmill at ~67% of their predicted maximum heart rate reserve. Immediately following treadmill exercise, subjects performed 25 minutes of resistance exercises including 2 sets of 12 reps at 67% of their 1RM of each exercise. Cool down consisted of five minutes on the treadmill with a gradual decline in speed. The energy used during the AT intervention was 431.2 ± 90.9 kcals compared to the RT intervention 398.3 ± 93.9 kcals. The mean difference was significant, (p =0.003). Based on the results of this study, aerobic exercise preceding resistance training has a greater impact on total energy consumption in females versus the reverse order.