Accelerating Post-exercise Muscle Glycogen Resynthesis in Humans: Impact of Combined Nutrient Intake and Intermittent Pneumatic Compression or Heat Therapy

• Compression sleeve (Device), also known as IPC: From foot to hip/groin on both legs with only 1 leg connected to pneumatic pump for 1 hour
• Heat therapy (Device): Custom leg garment with one leg heated by circulating hot water approx 40 degrees C, the other leg approx 32 degrees C (thermoneutral) for 1 hour
• Glycogen-depleting exercise session (Other): Prolonged intermittent high intensity running (LIST protocol)
• Nutrient Intake (beverage) (Other): Post-exercise, all participants will receive a beverage containing 1.0 g/kg carbohydrate and 0.3 g/kg protein from the mixture of Gatorade Recover Protein Shake and Gatorade Thirst Quencher
• Skeletal muscle biopsy (Procedure): Vastus lateralis muscle in the lower thigh will be obtained by the percutaneous needle technique

Primary outcomes

• Rate of glycogen resynthesis [Change from baseline to 1.5 hrs and 3.5 hrs post exercise bout. Biopsy 1 post-exercise pre nutrient intake 1 and compression (IPC) or heat, biopsy 2 post compression or heat, pre-nutrition intake 2, biopsy 3 at 210 min. Higher rate is better.]: Leg skeletal muscle glycogen level assessment using assay kit
• Muscle functional recovery: Skeletal muscle function [Change from pre-exercise to post-exercise and prior to biopsies and treatments, and 24 hours post exercise. Less fatigue is better.]: Work fatigue (%) of the knee extensors measured using an isokinetic dynamometer
• Muscle functional recovery: Perceived muscle soreness [Change from pre-exercise to post-exercise and prior to biopsies and treatments, and 24 hours post exercise. Less soreness is better.]: Knee extensor muscle soreness on a visual analog scale (VAS) of 100 mm after stepping on and off a 40 cm (female) or 45 cm (male) box three times

Secondary outcomes

• mRNA expression of genes involved in regulation of glucose and glycogen metabolism and muscle functional recovery [Change from baseline to 1.5 hours and 3.5 hours post exercise bout. Biopsy 1 post-exercise pre- nutrient intake 1 and compression (IPC) or heat, biopsy 2 post compression or heat and pre- nutrition intake 2, biopsy 3 at 210 min. Higher expression better.]: Leg skeletal muscle fiber analysis determined using RT-PCR (Real-time polymerase chain reaction)
• Serum insulin [Change from post exercise at same time as biopsy 1 (Time 0), biopsy 2 (1.5 hrs) and biopsy 3 (3.5 hrs)]: Blood test using ELISA kit
• Serum Glucose [Change from post exercise at same time as biopsy 1 (Time 0), biopsy 2 (1.5 hrs) and biopsy 3 (3.5 hrs]: Blood test using ELISA kit

Sex: All, ages: 18 Years to 35 Years, accepts healthy volunteers

Inclusion Criteria:

1. Subjects will be male and female participants in good health
2. 18-35 years of age
3. Currently performing cardiovascular or intermittent exercise at a moderate to high intensity at least 5 days per week for 60 minutes or longer per day.
4. Understanding of the procedures to be undertaken as part of the study
5. Willingness to participate in exercise testing and follow instructions provided by the experimenter
6. Informed, voluntary, written consent to participate in the study

Exclusion Criteria:

1. History of deep vein thrombosis
2. Obesity (BMI > 30 kg/m2)
3. Hypertension (resting SBP > 140/90 mmHg)
4. Smoking
5. Pregnant, planning to become pregnant, or lactating
6. Supplements containing antioxidants including vitamin C and E and N-acetyl cysteine
7. Any medication
8. Lactose intolerance
9. Participation in another study within the previous 30 days or in a PepsiCo funded study within the past 6 months.

• Bruno Roseguini, PhD, Principal investigator, Purdue University