Exertional Rhabdomyolysis in a 21-Year-Old Healthy Woman: A Case Report.

McKay, BD, Yeo, NM, Jenkins, NDM, Miramonti, AA, and Cramer, JT. Exertional rhabdomyolysis in a 21-year-old healthy woman: a case report. J Strength Cond Res 31(5): 1403-1410, 2017-The optimal resistance training program to elicit muscle hypertrophy has been recently debated and researched. Although 3 sets of 10 repetitions at 70-80% of the 1 repetition maximum (1RM) are widely recommended, recent studies have shown that low-load (∼30% 1RM) high-repetition (3 sets of 30-40 repetitions) resistance training can elicit similar muscular hypertrophy. Incidentally, this type of resistance training has gained popularity. In the process of testing this hypothesis in a research study in our laboratory, a subject was diagnosed with exertional rhabdomyolysis after completing a resistance training session that involved 3 sets to failure at 30% 1RM. Reviewed were the events leading up to and throughout the diagnosis of exertional rhabdomyolysis in a healthy recreationally-trained 21-year-old woman who was enrolled in a study that compared the acute effects of high-load low-repetition vs. low-load high-repetition resistance training. The subject completed a total of 143 repetitions of the bilateral dumbbell biceps curl exercise. Three days after exercise, she reported excessive muscle soreness and swelling and sought medical attention. She was briefly hospitalized and then discharged with instructions to take acetaminophen for soreness, drink plenty of water, rest, and monitor her creatine kinase (CK) concentrations. Changes in the subject's CK concentrations, ultrasound-determined muscle thickness, and echo intensity monitored over a 14-day period are reported. This case illustrates the potential risk of developing exertional rhabdomyolysis after a low-load high-repetition resistance training session in healthy, young, recreationally-trained women. The fact that exertional rhabdomyolysis is a possible outcome may warrant caution when prescribing this type of resistance exercise.

Effects of rumenic acid rich conjugated linoleic acid supplementation on cognitive function and handgrip performance in older men and women.

The purpose of this study was to investigate the effects of 8weeks at 6g per day of RAR CLA versus placebo on cognitive function and handgrip performance in older men and women. Sixty-five (43 women, 22 men) participants (mean±SD; age=72.4±5.9yrs; BMI=26.6±4.2kg·m-2) were randomly assigned to a RAR CLA (n=30: 10 men, 20 women) or placebo (PLA; high oleic sunflower oil; n=35: 12 men, 23 women) group in double-blind fashion and consumed 6g·d-1 of their allocated supplement for 8weeks. Before (Visit 1) and after supplementation (Visit 2), subjects completed the Serial Sevens Subtraction Test (S7), Trail Making Test Part A (TMA) and Part B (TMB), and Rey's Auditory Verbal Learning Test (RAVLT) to measure cognitive function. The RAVLT included 5, 15-item auditory word recalls (R1-5), an interference word recall (RB), a 6th word recall (R6), and a 15-item visual word recognition trial (RR). For handgrip performance, subjects completed maximal voluntary isometric handgrip strength (MVIC) testing before (MVICPRE) and after (MVICPOST) a handgrip fatigue test at 50% MVICPRE. Hand joint discomfort was measured during MVICPRE, MVICPOST, and the handgrip fatigue test. There were no treatment differences (p>0.05) for handgrip strength, handgrip fatigue, or cognitive function as measured by the Trail Making Test and Serial Seven's Subtraction Test in men or women. However, RAR CLA supplementation improved cognitive function as indicated by the RAVLT R5 in men. A qualitative examination of the mean change scores suggested that, compared to PLA, RAR CLA supplementation was associated with a small improvement in joint discomfort in both men and women. Longer-term studies are needed to more fully understand the potential impact of RAR CLA on cognitive function and hand joint discomfort in older adults, particularly in those with lower cognitive function.