Acute Study: Effects of Upper and Lower Body Wearable Resistance on Spatio-temporal and Kinetic Parameters During Running

Couture, Simperingham (6)

 

Purpose Statement:

This study compared the effects of different WR placements on steady state treadmill running performance.

 

Introduction:

WR of 1-10% BM was attached to either the upper, lower, or whole-body (Figure 1) during treadmill running (3.9 m/s). Twelve recreational trained/ sport science student subjects were randomly assigned to five minutes of treadmill running with each WR condition: 1% BM lower body. 3% BM lower body, 5% BM lower body, 5% BM upper body, 5 % BM whole body, 10% BM whole body.

 

Key Findings:

  1. 5% BM and greater WR loads caused significant changes in vertical stiffness, vertical and horizontal force, and impulse.
  2. Functional and effective propulsive force (3.0%, 2.8%) and impulse (2.9%, 3.5%) were significantly greater with lower 5% BM than upper 5% BM.
  3. The lower body 5% BM (2.2%) and whole body 10% BM (4.9%) conditions resulted in the lowest relative increase in functional peak vGRF compared to increase in BM (Figure 3).
  4. Only significant spatiotemporal change was to contact time, which increased (2.9%) with whole body 10% BM.
  5. Heart rate was significantly greater with all WR conditions (5.4-8.8%) and RPE significantly greater with lower 5% BM (27.9%) and whole body 10% BM (32.6%).

Figure 3: A comparison of percent increase in functional vertical impulse and  functional peak vGRF

 

Practical Applications:

  1. WR may be used to increase forces and muscular stimulus without negatively effecting normal running gait.
  2. A runner with an overly “bouncy” stride (excessive vertical motion), may benefit from lower body WR to increase horizontal force.
  3. A runner with a long, low stride may benefit from upper body WR to increase vertical force and balancing out the trajectory may be more beneficial.

 

Link to Publication

 

Acute Study: Acute Metabolic Changes with Thigh-Positioned Wearable Resistances during Submaximal Running in Endurance-Trained Runners

Field, Gill (7)

 

Purpose Statement:

Investigate how a magnitude of between 1% and 5% BM WR attached to the thigh affects the acute metabolic responses to submaximal running in endurance trained runners

 

Introduction:

In recreational distance runners, heavy resistance, explosive resistance and muscle endurance resistance training have been found to significantly improve running performance. At elite levels, concepts of progressive overload and specificity become more important. Twenty endurance-trained runners performed four sessions (Figure 4); familiarization and three testing sessions on a motorized treadmill with different thigh loading schemes (0% [unloaded], 1%, 2%, 3%, 4%, 5%). Metabolic response measures of HR response, oxygen consumption (VO2), lactate accumulation (LA), training load score (TLS)(combination of avgHR, intensity factor, VT2 – point which LA accumulation exceeds clearance), and rate of perceived exertion (RPE).

 

Figure 4: Structure of Testing Sessions

 

Key Findings:

  1. There is an expected 1.59% (± 0.62) increase in VO2 for every 1% BM of additional thigh load
  2. There is an expected 0.63% (± 0.32) increase in acute HR for every 1% BM of additional thigh load
  3. Loads at 3% and 4% BM reported very likely large increases in lactate accumulation (0.41 ± 0.18 and 0.42 ± 0.19 respectively) with mean accumulations of 3.27 (±1.79) and 3.30 mmol/L (±2.03) respectively and most likely very large increase at 5% BM (3.52 mmol/L)(Figure 5)
  4. Both 4% and 5% BM reported most likely very large increases in RPE (0.82 ± 0.29 and 0.86 ± 0.28 respectively), with mean reported scores of 4.20 (±1.26) and 4.38 (±1.57) respectively (Figure 5)

 

Figure 5: Lactate Accumulation and Rate of Perceived Exertion (0% – 5% BM)

Practical Applications:

  1. Limb loading during locomotion can increase metabolic cost compared to unloaded
  2. When WR is attached to the thighs, great VO2 changes occur compared to trunk placement, most likely due to greater inertial demands from distal thigh loading
  3. Loads of at least 2% and 3% BM are needed to see substantial increases in HR and VO2
  4. WR attached to the legs enable a running-specific form of resistance training to be incorporated into training programming

 

Link to Publication

 

Acute Study: Acute Metabolic Changes with Lower Leg-Positioned Wearable Resistances during Submaximal Running in Endurance-Trained Runners

Field, Gill (8)

Purpose Statement:

Investigate how a magnitude of between 0% and 2.55% BM WR attached to the calf affects the acute metabolic responses to submaximal running in endurance trained runners

 

Introduction:

In recreational distance runners, heavy resistance, explosive resistance and muscle endurance resistance training have been found to significantly improve running performance. At elite levels, concepts of progressive overload and specificity become more important. Twenty endurance-trained runners performed four sessions (Figure 4); familiarization and three testing sessions on a motorized treadmill with different calf loading schemes (0% [unloaded], 0.5%, 1.0%, 1.5%, 2%, 2.5%). Metabolic response measures of HR response, oxygen consumption (VO2), lactate accumulation (LA), training load score (TLS)(combination of avgHR, intensity factor, VT2 – point which LA accumulation exceeds clearance), and rate of perceived exertion (RPE).

 

Figure 6: Structure of Testing Sessions

 

Figure 7: Example of lower-leg wearable resistance loading pattern (0.5%) for a 70kg runner

 

Figure 8: Example of lower-leg wearable resistance loading pattern (1.5%) for a 70kg runner

 

Figure 9: Example of lower-leg wearable resistance loading pattern (2.5%) for a 70kg runner

Key Findings:

  1. There is an expected 2.56% (± 0.75) increase in VO2 for every 1% BM of additional calf load
  2. There is an expected 1.16% (± 0.52) increase in acute HR for every 1% BM of additional calf load
  3. There is an expected 0.39% (± 0.06) increase in exercise stress for the equivalent of 10-min of running for every 1% BM of additional calf load
  4. There were most likely very large increases in both acute lactate accumulation and RPE with 2.5% and greater BM of calf loading

 

Figure 10: Lactate Accumulation and Rate of Perceived Exertion (0% – 5% BM)

 

Practical Applications:

  1. Limb loading during locomotion can increase metabolic cost compared to unloaded
  2. When WR is attached to the thighs, great VO2 changes occur compared to trunk placement, most likely due to greater inertial demands from distal thigh loading
  3. Loads of at least 2% and 3% BM are needed to see substantial increases in HR and VO2
  4. WR attached to the legs enable a running-specific form of resistance training to be incorporated into training programming

 

Link to Publication

 

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