The affective and behavioral responses to repeated “strength snacks”

Background A training program consisting of only one-repetition maximum (1RM) training results in similar strength adaptations as traditional resistance exercise. However, little is known regarding the affective or behavioral responses to this type of training. Aim To examine the affective and behavioral response to either a traditional resistance exercise program or a biweekly 1RM-training program. Methods Participants were trained for 8 weeks (2× per week). The HYPER group completed four sets of 8–12 repetitions; the 1RM group (TEST) worked up to a single maximal repetition. Results The TEST group felt more revitalized and had an increase in positive engagement during their first visit, whereas the HYPER group showed an increase in feelings of physical exhaustion during their first and last visits. There were no pre to post differences for the change in behavior or self-efficacy between groups. Conclusion 1RM training appears to elicit a more favorable affective response, compared with HYPER training, which may ultimately improve adherence to resistance-type exercise

Are higher blood flow restriction pressures more beneficial when lower loads are used?

The application of blood flow restriction during low-load resistance exercise has been shown to induce muscle growth with high or low restriction pressures, however, loads lower than 20% one-repetition maximum (1RM) remain unexplored. Fourteen trained individuals completed six elbow flexion protocols involving three different loads (10%, 15%, and 20% 1RM) each of which was performed with either a low (40% arterial occlusion) or high (80% arterial occlusion) pressure. Pre- and post-measurements of surface electromyography (sEMG), isometric torque, and muscle thickness were analyzed. An interaction was present for torque (p < 0.001) and muscle thickness (p < 0.001) illustrating that all increases in pressure and/or load resulted in a greater fatigue and muscle thickness. There was no interaction for sEMG (p = 0.832); however, there were main effects of condition (p = 0.002) and time (p = 0.019) illustrating greater sEMG in the 20% 1RM conditions. Higher blood flow restriction pressures may be more beneficial for muscle growth when very low loads are used

The acute muscular response to two distinct blood flow restriction protocols

The purpose of this study was to determine acute physiological and perceptual responses to two commonly implemented blood flow restriction protocols. Using a within-subject design, 15 participants (age ∼25) performed four sets of unilateral elbow flexion with each arm. One arm exercised using a 3-cm elastic cuff inflated to 160 mmHg, whereas the other arm exercised using a 5-cm nylon cuff inflated to 40% of the individual’s arterial occlusion pressure. While both protocols elicited increases in acute muscle thickness [pre: 4.5 (0.2) cm, post: 5.0 (0.2) cm; p < 0.001] and electromyography amplitude [first 3 reps: 55 (5) %MVC; last 3 reps: 87 (10) %MVC], there were no differences between conditions. Both protocols produced decreases in post-exercise strength (pre: 70 Nm, post: 51 Nm; p < 0.001) with no difference between conditions. The nylon protocol resulted in more repetitions during sets 2 [13 (2) vs. 9 (4); p = 0.001] and 3 [10 (2) vs. 7 (4); p = 0.05], while producing lower levels of discomfort following each set (average 3 vs. 4; p < 0.05). In conclusion, both protocols produced similar acute responses thought to be important for promoting muscle growth. However, the use of arbitrary pressures may place some individuals under complete arterial occlusion which may increase the potential risk of an adverse event

A higher effort-based paradigm in physical activity and exercise for public health: making the case for a greater emphasis on resistance training

It is well known that physical activity and exercise is associated with a lower risk of a range of morbidities and all-cause mortality. Further, it appears that risk reductions are greater when physical activity and/or exercise is performed at a higher intensity of effort. Why this may be the case is perhaps explained by the accumulating evidence linking physical fitness and performance outcomes (e.g. cardiorespiratory fitness, strength, and muscle mass) also to morbidity and mortality risk. Current guidelines about the performance of moderate/vigorous physical activity using aerobic exercise modes focuses upon the accumulation of a minimum volume of physical activity and/or exercise, and have thus far produced disappointing outcomes. As such there has been increased interest in the use of higher effort physical activity and exercise as being potentially more efficacious. Though there is currently debate as to the effectiveness of public health prescription based around higher effort physical activity and exercise, most discussion around this has focused upon modes considered to be traditionally ‘aerobic’ (e.g. running, cycling, rowing, swimming etc.). A mode customarily performed to a relatively high intensity of effort that we believe has been overlooked is resistance training. Current guidelines do include recommendations to engage in ‘muscle strengthening activities’ though there has been very little emphasis upon these modes in either research or public health effort. As such the purpose of this debate article is to discuss the emerging higher effort paradigm in physical activity and exercise for public health and to make a case for why there should be a greater emphasis placed upon resistance training as a mode in this paradigm shift