Electromyographical comparison of the abdominal crunch to planks performed with and without a suspension trainer

Research has shown the importance of strengthening the abdominal muscles for increased stability, mobility, rehabilitation and prevention of lower back pain as well as increased athletic performance. Understanding the relative recruitment of the abdominal muscles during the performance of various abdominal exercises can aid rehabilitation specialists, personal trainers and athletic coaches in selecting appropriate exercises for clients and athletes with different needs and varying fitness levels. Eleven participants took part in a study which purpose was to compare the relative recruitment of the rectus abdominis (RA), external oblique (EO), and rectus femoris (RF) during the performance of six different exercises: the traditional abdominal crunch, an isometric plank (traditional and suspended), mountain climber plank (traditional and suspended) and a suspended plank with a knee tuck. Repeated measures ANOVA found a main effect for muscle and exercise (p 0.05) as well as a significant interaction between these factors (p 0.05). We found that the relative recruitment of the RA and EO was similar among the crunch, plank, and TRX plank. Our results also indicated that the TRX knee tuck produced significantly greater overall muscle activity than the other exercise conditions (p 0.05). We conclude that for individuals wanting to develop the abdominal musculature, all plank variations (traditional and suspended) seem to be effective.