Which Muscle Groups Need Work As We Age?

Introduction

We know by our own experience and looking at veteran track and field records at state, national and world level that masters athletes get slower with age. We also know muscle mass and strength and power of the lower limb muscles decreases, thus compromising both our strength and power that can be applied by the muscles to move us forward during sprinting.

During walking, we know that the plantar flexor (push-off muscles) reduce in power as we age and we rely more on the hip and knee extension muscles to walk at any speed.

As we move from walking to running, we need over twice the ground reaction force to be generated by the lower limb muscles. Research has shown that in veteran sprint runners, at any given speed, the vets have a lower ground reaction force and take shorter steps at a higher stride frequency than younger sprinters. Research has also shown that vets demonstrate greater knee flexion (bending) at initial ground contact, but lower knee bending during the first half of the stance phase. Vets also have increased ground contact time compared to younger sprinters.

Only a few studies have compared lower limb joint kinetics in young versus veteran runners. Both showed that the vets have lower power generation in the ankles but have similar power generation in the knees and hips. However, these two studies looked at running speeds of 2.7 m/sec (9.7 km/hr), not sprint running speeds.

Recently, some Finnish sport scientists, one a good buddy of mine, examined power outputs at the ankles, knees and hips during walking, running and sprinting in competitive male athletes (sprinters and long jumpers).

The Research

They compared three age-groups: young (26±6 years), middle-aged (61±5 years) and old (78±4 years) with 13 runners in each age group. Each athlete did three walking trials at a self-selected speed, three running trials at 4 m/sec (14.4 km/hr) and then two 60 m sprint efforts at their maximum speed. The researchers used an 8-camera video-recording system with markers attached to joints plus five force platforms to record joint angles and ground reaction forces.

The Results

The researchers found age-related decreases in ankle plantar flexor power generation became greater as speed changes from walking to running to sprinting. As a result, the older sprinters generated relatively more power at the knee and hip extensors than their younger counterparts when walking and running at the same speed. During maximal sprinting, young adults with faster top speeds demonstrate greater power outputs from the ankle and hip joints, but interestingly, not from the knee joint when compared with the middle-aged and old adults.

 So What?

Taken together, these findings show that decreases in ankle power contributes most to the age-related decline in running and sprinting speed. In addition, reduced muscular output from the hip rather than from knee limits the sprinting performance in older age.

This means that veteran power athletes need to put a greater emphasis on ankle and hip power development. This strongly suggests a combination of plyometric and power-focused resistance training in the gym is critical for the veteran track and field athlete and maybe sprinters in other sports. Specific exercises to develop ankle, knee and hip strength and power are shown in Table 1 below.

Table 1: Gym-based and plyometric exercises to develop ankle, knee and hip strength and power.

Joint

Gym-Based Exercises

Plyometrics

Ankle

Calf raises, Inverted leg press with plantar flexion, Squats with   plantar flexion.

Quick feet drills using ladders, two legged jumps > hops, two-legged   box-jumps > single legged box-jumps

Knee

Squats, Push press (front), Split squat, Inverted leg press, Lunges,   Power cleans

Cone hops, double-legged jumps, standing triple jumps, bounding, step   jumps, hurdle jumps, squat jumps

Hip

Squats, Push press (front), Split squat, Inverted leg press, Lunges,   Power cleans, Hip flexors

Cone hops, double-legged jumps, standing triple jumps, bounding, step   jumps, hurdle jumps, squat jumps, hill sprints, sled drives

 

I strongly recommend the advice and input of both a sports physiotherapist (to examine veteran athlete muscle weaknesses and imbalances) and a strength and conditioning expert to develop a specific gym-based and plyometric training program for each individual athlete.

Critically, ensure you make them aware that the older the veteran athlete, the greater the emphasis needs to be on ankle and hip strength and power development.

For more information on developing speed, strength and power, check out chapters 7 (Strength and power training for the masters athlete) and 8 (Speed and power training for the masters athlete). Two of 18 highly applied and evidence-based chapters from my book The Masters Athlete. The book and individual chapters are available as pdf’s too.

Source: Kulmala, J-P. and others (2014). Which muscles compromise human locomotor performance with age? Journal of the Royal Society Interface, 11: 20140858.