The feasibility, safety, and efficacy of lower limb garment-integrated blood flow restriction training in healthy adults.

OBJECTIVES: Explore the feasibility of lower-limb garment-integrated BFR-training. DESIGN: Observational study. SETTING: Human performance laboratory. PARTICIPANTS: Healthy males with no experience of BFR-training. MAIN OUTCOME MEASURES: Feasibility was determined by a priori thresholds for recruitment, adherence, and data collection. Safety was determined by measuring BFR torniquet pressure and the incidence of side effects. Efficacy was determined by measuring body anthropometry and knee isokinetic dynamometry. Feasibility and safety outcomes were reported descriptively or as a proportion with 95% confidence intervals (95% CI), with mean change, 95% CIs, and effect sizes for efficacy outcomes. RESULTS: Twelve participants (mean age 24.8 years [6.5]) were successfully recruited; 11 completed the study. 134/136 sessions were completed (adherence = 98.5%) and 100% of data were collected. There was one event of excessive pain during exercise (0.7%, 95% CI 0.0%, 4.0%), two events of excessive pain post-exercise (1.5%, 95% CI 0.4%, 5.5%), and one event of persistent paraesthesia post-exercise (0.7%, 95% CI 0.0%, 4.0%). Mean maximal BFR torniquet pressure was <200 mmHg. We observed an increase in knee extension peak torque (mean change 12.4 Nm), but no notable changes in body anthropometry. CONCLUSIONS: Lower-limb garment-integrated BFR-training is feasible, has no signal of important harm, and could be used independently.

Performance comparison of the MOXY and PortaMon near-infrared spectroscopy muscle oximeters at rest and during exercise.

The purpose of the study was to compare muscle oxygenation as measured by two portable, wireless near-infrared spectroscopy (NIRS) devices under resting and dynamic conditions. A recently developed low-cost NIRS device (MOXY) was compared against an established PortaMon system that makes use of the spatially resolved spectroscopy algorithm. The influence of increasing external pressure on tissue oxygen saturation index (TSI) indicated that both devices are stable between 2 and 20 mmHg. However, above this pressure, MOXY reports declining TSI values. Analysis of adipose tissue thickness (ATT) and TSI shows a significant, nonlinear difference between devices at rest. The devices report similar TSI (%) values at a low ATT (<7 mm) (PortaMon minus MOXY difference is +1.1±2.8%) with the major subsequent change between the devices occurring between 7 and 10 mm; at ATT values >10 mm the difference remains constant (-14.7±2.8%). The most likely explanation for this difference is the small source-detector separation (2.5 cm) in the MOXY resulting in lower tissue penetration into muscle in subjects with higher ATT. Interday test-retest reliability of resting TSI was evaluated on five separate occasions, with the PortaMon reporting a lower coefficient of variation (1.8% to 2.5% versus 5.7% to 6.2%). In studies on male subjects with low ATT, decreases in the TSI were strongly correlated during isometric exercise, arterial occlusion, and incremental arm crank exercise. However, the MOXY reports a greater dynamic range, particularly during ischemia induced by isometric contraction or occlusion (Δ74.3% versus Δ43.7%; hyperemia MAX-occlusion MIN). This study shows that in this subject group both MOXY and PortaMon produce physiologically credible TSI measures during rest and exercise. However, the absolute values obtained during exercise are generally not comparable between devices unless corrected by physiological calibration following an arterial occlusion.

Applied Sports Nutrition Support, Dietary Intake and Body Composition Changes of a Female Athlete Completing 26 Marathons in 26 Days: A Case Study.

The aim of this case study is to describe the nutrition practices of a female recreational runner (VO2max 48.9 ml·kg-1·min-1) who completed 26 marathons (42.195 km) in 26 consecutive days. Information relating to the nutritional intake of female runners during multi-day endurance events is extremely limited, yet the number of people participating year-on-year continues to increase. This case study reports the nutrition intervention, dietary intake, body composition changes and performance in the lead-up and during the 26 days. Prior to undertaking the 26 marathon challenge, three consultations were held between the athlete and a sports nutrition advisor; planning and tailoring the general diet and race-specific strategies to the endurance challenge. During the marathons, the mean energy and fluid intake was 1039.7 ± 207.9 kcal (607.1 - 1453.2) and 2.39 ± 0.35 L (1.98 - 3.19). Mean hourly carbohydrate intake was 38.9 g·hr-1. 11 days following the completion of the 26 marathons, body mass had reduced by 4.6 kg and lean body mass increasing by 0.53 kg when compared with 20 days prior. This case study highlights the importance of providing general and event-specific nutrition education when training for such an event. This is particularly prudent for multi-day endurance running events.