RESEARCH: studies I shared this week: 19-25 September 2022

All of the studies I've shared (~500 studies) are available on the RESOURCES PAGE.

TRAINING: Effects of six weeks outdoor versus treadmill running on physical fitness and body composition in recreationally active young males


  1. The aim of this pilot study was to compare the effects of 6-weeks of supervised outdoor running (OT) vs treadmill running (TT) on physical fitness and body composition in recreationally active young males.
  2. Significant time-effect was found in all physical fitness variables, body mass, BMI, body fat percentage, and leg skeletal muscle mass (SMM).
  3. Both OT and TT improved physical fitness and decreased fat percentage. However, compared to TT, the OT intervention preserved leg SMM and induced greater physical fitness improvements.

PRACTICAL TAKEAWAY - using a treadmill is a useful when it may not be possible to run outdoors or to add mileage at the end of a training day. However, there are some compromises compared to running outdoors and it is important to take these into consideration when planning training.

INTERVALS: Effects of Work and Recovery Duration and Their Ratio on Cardiorespiratory and Metabolic Responses During Aerobic Interval Exercise


  1. Twelve men (22.1 ± 1 year) executed, until exhaustion, 4 interval protocols at an intensity corresponding to 100% of maximal aerobic velocity. Two protocols were performed with work bout duration of 120 seconds and recovery durations of 120 (WRR: 1:1) or 60 seconds (WRR: 2:1), and 2 protocols with work bout duration of 60 seconds and recovery durations of 60 (WRR: 1:1) or 30 seconds (WRR: 2:1).
  2. When compared at equal exercise time, total V̇ o2 and exercise time at V̇ o2 above 80, 90, and 95% of V̇ o2 max were longer in 120:120, 120:60 and 60:30 vs. the 60:60 protocol.
  3. When analyzed for total exercise time (until exhaustion), total V̇ o2 was higher in the 60:60 compared with all other protocols, and in the 120:120 compared with 120:60.
  4. When interval exercise protocols are executed at similar effort (until exhaustion), work and recovery durations do not, in general, affect exercise time at high oxygen consumption and HR rates.
  5. However, as work duration decreases, a higher work-to-recovery ratio (e.g., 2:1) should be used to achieve and maintain high (>95% of maximum) cardiorespiratory stimulus.
  6. Longer work bouts and higher work-to-recovery ratio seem to activate anaerobic glycolysis to a greater extent, as suggested by greater blood lactate concentrations.

PRACTICAL TAKEAWAY - when planning interval sessions it is important to consider the duration of both the work and rest intervals. Intervals of 60" or 120" appear superior to 30" intervals and work:rest rations of 2:1 appear superior. Therefore some sessions to use would be 120" work, 60" rest or 60" work, 30" rest until exhaustion.

NUTRITION: An acute bout of swimming increases post-exercise energy intake in young healthy men and women


  1. This study compared the acute effects of swimming on appetite, energy intake, and food preference and reward, versus exertion-matched cycling and a resting control.
  2. The exercise trials involved 60-min of 'hard' exercise (self-selected rating of perceived exertion: 15) performed 90-min after a standardised breakfast.
  3. Compared with control (3259 ± 1265 kJ), swimming increased ad libitum energy intake (3857 ± 1611 kJ); the magnitude of increase was smaller after cycling (3652 ± 1619 kJ).
  4. This study has identified an orexigenic effect of swimming.

PRACTICAL TAKEAWAY - hunger after swimming training is greater than after other modalities. Depending on your diet and nutrition goals it would be valuable to keep this in mind when planning post-training meals.

PHYSIOLOGY: Glucose metabolism responds to perceived sugar intake more than actual sugar intake


  1. Thirty participants who have type 2 diabetes consume beverages that have identical ingredients but have deceptive nutrition facts labels.
  2. Blood glucose levels measured four times before and after beverage consumption show that blood glucose levels increase when participants believe the beverage has high sugar content as portrayed on the labels.
  3. The study results support the concept of anticipatory budgeting on glucose metabolism.

PRACTICAL TAKEAWAY - the psychobiological model is real and can impact how our body responds to what we eat. Be mindful of what you eat and know that reading the label can have a impact on your body's response.

STRENGTH: Short-term aerobic conditioning prior to resistance training augments muscle hypertrophy and satellite cell content in healthy young men and women


  1. Fourteen healthy young (22 ± 2 years) men and women underwent aerobic conditioning (AC) via 6 weeks of unilateral cycling followed by 10 weeks of bilateral resistance training (RT) to investigate how AC alters SC content, activity, and muscle hypertrophy following RT.
  2. Type I and type II fiber cross-sectional area (CSA) increased following RT, and when legs were analyzed independently, AC + RT increased type I, type II, and mixed-fiber CSA, where the RT leg tended to increase type II.
  3. Those with the greatest capillary-to-fiber perimeter exchange index before RT had the greatest change in CSA following RT and a significant relationship was observed between type II fiber capillarization and the change in type II-fiber CSA with RT.
  4. This study demonstrates that AC prior to RT can augment RT-induced muscle adaptions and that these differences are associated with increases in capillarization.

PRACTICAL TAKEAWAY - to optimize the returns from a block of resistance training, it is important to ensure that your body is in the ideal state to make these adaptations. A period of aerobic training can increase capillarization and create the ideal state for adaptation to resistance training stimulus.

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