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Beef powder is a new high-quality protein source scarcely researched relative to exercise performance. The present study examined the impact of ingesting hydrolyzed beef protein, whey protein, and carbohydrate on strength performance (1RM), body composition (via plethysmography), limb circumferences and muscular thickness (via ultrasonography), following an 8-week resistance-training program. After being randomly assigned to one of the following groups: Beef, Whey, or Carbohydrate, twenty four recreationally physically active males (n = 8 per treatment) ingested 20 g of supplement, mixed with orange juice, once a day (immediately after workout or before breakfast). Post intervention changes were examined as percent change and 95% CIs. Beef (2.0%, CI, 0.2–2.38%) and Whey (1.4%, CI, 0.2–2.6%) but not Carbohydrate (0.0%, CI, -1.2–1.2%) increased fat-free mass. All groups increased vastus medialis thickness: Beef (11.1%, CI, 6.3–15.9%), Whey (12.1%, CI, 4.0, -20.2%), Carbohydrate (6.3%, CI, 1.9–10.6%). Beef (11.2%, CI, 5.9–16.5%) and Carbohydrate (4.5%, CI, 1.6–7.4%), but not Whey (1.1%, CI, -1.7–4.0%), increased biceps brachialis thickness, while only Beef increased arm (4.8%, CI, 2.3–7.3%) and thigh (11.2%, 95%CI 0.4–5.9%) circumferences. Although the three groups significantly improved 1RM Squat (Beef 21.6%, CI 5.5–37.7%; Whey 14.6%, CI, 5.9–23.3%; Carbohydrate 19.6%, CI, 2.2–37.1%), for the 1RM bench press the improvements were significant for Beef (15.8% CI 7.0–24.7%) and Whey (5.8%, CI, 1.7–9.8%) but not for carbohydrate (11.4%, CI, -0.9-23.6%). Protein-carbohydrate supplementation supports fat-free mass accretion and lower body hypertrophy. Hydrolyzed beef promotes upper body hypertrophy along with similar performance outcomes as observed when supplementing with whey isolate or maltodextrin.

The impact of animal protein blend supplements in endurance athletes is scarcely researched. The authors investigated the effect of ingesting an admixture providing orange juice and protein (PRO) from beef and whey versus carbohydrate alone on body composition and performance over a 10-week training period in male endurance athletes. Participants were randomly assigned to a protein (CHO + PRO, n = 15) or a nonprotein isoenergetic carbohydrate (CHO, n = 15) group. Twenty grams of supplement mixed with orange juice was ingested postworkout or before breakfast on nontraining days. Measurements were performed pre- and postintervention on body composition (by dual-energy X-ray absorptiometry), peak oxygen consumption ($\dot{\mathrm{V}}{\mathrm{O}}_2\text{peak}$), and maximal aerobic speed. Twenty-five participants (CHO + PRO, n = 12; CHO, n = 13) completed the study. Only the CHO + PRO group significantly (p < .05) reduced whole-body fat (mean ± SD) (−1.02 ± 0.6 kg), total trunk fat (−0.81 ± 0.9 kg), and increased total lower body lean mass (+0.52 ± 0.7 kg), showing close to statistically significant increases of whole-body lean mass (+0.57 ± 0.8 kg, p = .055). Both groups reduced (p < .05) visceral fat (CHO + PRO, −0.03 ± 0.1 kg; CHO, −0.03 ± 0.5 kg) and improved the speed at maximal aerobic speed (CHO + PRO, +0.56 ± 0.5 km/hr; CHO, +0.35 ± 0.5 km/hr). Although consuming animal protein blend mixed with orange juice over 10 weeks helped to reduce fat mass and to increase lean mass, no additional performance benefits in endurance runners were observed.

Purpose: To investigate single-day time-to-exhaustion (TTE) and time-trial (TT) -based laboratory tests values of critical power (CP), W prime (W′), and respective oxygen-uptake-kinetic responses. Methods: Twelve cyclists performed a maximal ramp test followed by 3 TTE and 3 TT efforts interspersed by 60 min recovery between efforts. Oxygen uptake ($\dot{\mathrm{V}}{\mathrm{O}}_2$) was measured during all trials. The mean response time was calculated as a description of the overall $\dot{\mathrm{V}}{\mathrm{O}}_2$-kinetic response from the onset to 2 min of exercise. Results: TTE-determined CP was 279 ± 52 W, and TT-determined CP was 276 ± 50 W (P = .237). Values of W′ were 14.3 ± 3.4 kJ (TTE W′) and 16.5 ± 4.2 kJ (TT W′) (P = .028). While a high level of agreement (−12 to 17 W) and a low prediction error of 2.7% were established for CP, for W′ limits of agreements were markedly lower (−8 to 3.7 kJ), with a prediction error of 18.8%. The mean standard error for TTE CP values was significantly higher than that for TT CP values (2.4% ± 1.9% vs 1.2% ± 0.7% W). The standard errors for TTE W′ and TT W′ were 11.2% ± 8.1% and 5.6% ± 3.6%, respectively. The $\dot{\mathrm{V}}{\mathrm{O}}_2$ response was significantly faster during TT (~22 s) than TTE (~28 s). Conclusions: The TT protocol with a 60-min recovery period offers a valid, time-saving, and less error-filled alternative to conventional and more recent testing methods. Results, however, cannot be transferred to W′.