S2 lab 4 - increased non-contractile mass on VO2, power output and energy expenditure

what is non-contractile mass

mass that does not generate force (e.g. external load)

intervention condition

add 20% body mass load

treadmill protocol

2 stages (4min each) at 5km/h

inclines used

s1 = 2%, s2 = 8%

when are measurements collected

final minute of each stage

work rate equation (treadmill)

work = m x g x v x slope

effect of added mass on VO2

increased oxygen uptake

effect on energy expendituyre

increases energy cost

effect on jump performance

decreases height and power

why repeat in both conditions

compare control vs intervention effects

how were oxygen uptake and energy expenditure affected by increasing non-contractile mass by 20%

increases by 20%-linear relationship

speed and gradient remains the same

what is the clinical relevance of studying the physiological responses to carrying additional non-contractile mass?

resistance training

obesity management

rehab programs

which other population groups would this type of research be relevant for? Which other population groups carry additional non-contractile mass?

elderly-sarcopenia

obese

pregnant women

military/emergency services

what was the effect of carrying additional non-contractile mass on jump height and power? Can you explain your answers by referring to the relationship between force and velocity and the relationship between force, velocity and power

increased power-dependent on person, weight increase can mean less power is produced

reduced jump height-as power increases, velocity decrease

power = force x velocity, more force is needed

greater force production at take off

based on knowledge from the Hunter et al 2015 paper, how could our measurement of energy expenditure during treadmill walking have been improved?

Oxygen uptake was measured during the first 5 min of exercise, between the 20th and 25th minutes of exercise, and between the 35th and 40th minutes of exercise, and averaged. Oxygen uptake was converted into kilocalories per session (5 kcal × L O₂·min⁻¹ × 40 min).

according to the hunter et al. paper, why does resting energy expenditure decrease following weight loss and which type of training is most likely to prevent this?

the body becomes more efficient at using energy

prevented by resistance training